How to sync app data across multiple i-devices? - ios

I am new to iOS app development and am interested in developing an app that needs to utilize existing technologies to sync app specific data across multiple i-devices (iPhone, iPad, Touch, etc.). As an example, the app can be installed on multiple devices. On one device, the user will initially create an account. Then in subsequent logins, the user may create a task list, and each task item may possibly include a captured photo image. On the user's second i-device, as he logs in, he would be able to see and access the list and images (locally). Can someone explain to me what technologies I can leverage on to implement such an app?
Specifically:
How do I set up and manage the user accounts? Do I Need a dedicated server and sql database set up for my entire user base? And what programming/scripting languages do I need to learn?
How about the mechanism of pushing and pulling app data from one device to another? Do I need some kind of cloud technologies (SaaS?) to handle the storage and transferring of the data?
Any specific open source or commercial products I can leverage on?
Thanks in advance.
Kenny

I personally have not have had a situation like this, but here is what I would recommend.
You will need to have a server set up with database software.
You will need to write an api for yourself based on HTTP POST (REST) or maybe you could write a SOAP service.
I would HIGHLY recommend purchasing an SSL cert. for your server that way you can send the username and password in your request and it will be encrypted automatically.
For the api, you have a whole selection of languages and databases at your disposal. I am personally biased towards asp net with an MSSQL server.
with your api you will need to write methods to authenticate the user, and then save and send your data.
In your app you will simply send web requests to the server (ASIHttpRequest maybe?) and you can receive JSON responses back, which you can then deserialize into workable objects and vice versa.
if you do use asp net, you can use the newtonsoft JSON library to convert your objects for sending and convert received objects.
I dont remember the name, but there also is a JSON library for obj-c that is usable on iPhone.

Use a SQL server and host a database of logins and passwords.
Then, from each device, create a connection to the server, and download the login information for the account.
Also, not to be rude but: Google it.

Related

What is the proper way to get private data from a MySQL database to an iOS app?

I am currently developing an app for a friend's business (so it's clear that I am not a professional developer and he's not going to get the perfect app). He needs the app to display and be able to interact with data from a MySQL database. I have already tried to find a way to do this but they mostly include a PHP script that just generates a json document which the app can then read. I cannot do that because the data includes customer information that can't just be accessible like that without some form of authentication from the app. The app will only be used by employees at work and on specific devices so storing the data locally is not a problem. Is there maybe a way to create a local cache of the database and then work with that? I would also be open to use other database software that can handle spreadsheet-like data.
Thanks in advance for any response!
Assuming your app going to get JSON data through PHP API. In that case, PHP API should encrypt the JSON data and your app will decrypt it. If you want to protect your data on users device, one of the option to use cipher SQLite.
You can any use symmetric or asymmetric encryption technique to encrypt the API response.
Here is good post to read.
https://www.ssl2buy.com/wiki/symmetric-vs-asymmetric-encryption-what-are-differences

Is it possible to substitute a server backend using Dropbox?

I am developing an iOS application (to be deployed on the App Store) that requires content updates on a weekly basis.
I understand that the best way to achieve this would be to use a server, where the app would query for new data and download responses in JSON. However I am not knowledgeable when it comes to HTML, PHP or MySQL and therefore am endeavoring to find an alternative.
Here's an idea: using Dropbox to substitute for a server backend. My app connects to one central Dropbox account, checks for new files, and downloads them if present.
Is this idea feasible? If not, are there any alternatives?
Dropbox cannot be a dependable substitute for your server/backend for following reasons:
Dropbox uses OAuth for authentication, which needs user interaction. You do not want your app users to go through Dropbox authentication with your 'common' credentials.
Users who have a Dropbox account or the app installed, will most likely use their own credentials to login which completely breaks your flow.
Drobox, although a good way of sharing and syncing files is not meant for more meaningful data like web services etc or user/database interaction etc. Just syncing JSON file may suffice your app's needs for now but from a long term perspective you want a proper back end.
As suggested in the comment by #tkanzakic you can use one of the substitution services if you don't want to get too technical on the backend.
I am pretty late to the party, but this is possible and not necessarily a stupid idea (though this depends on what you need). You might want to have a look at remote storage for example, which allows you to use Dropbox among other providers as backend.
For sure, you can use the Dropbox Sync API to achieve this (https://www.dropbox.com/developers/sync).

CloudKit - no server-side logic?

With CloudKit, you can focus on your client-side app development and let iCloud eliminate the need to write server-side application logic. CloudKit provides you with Authentication, private and public database, structured and asset storage services — all for free with very high limits.
You cannot upload any code to run on Apple's servers?
I've heard it being compared to Google App Engine and other cloud computing platforms, but without the ability to run your own code, isn't the whole thing pretty limited and not really comparable?
For example, if I want to build a news app which periodically pushes stories on topics that the user is interested, then this can't be done just using CloudKit because I would need scheduled jobs and data processing on the server.
Any thoughts?
Server-side
As you said CloudKit doesn't allow server-side code.
But there are possibilities.
Crons
You don't want to connect to the iCloud Dashboard everyday in order to perform the push by adding a record. One solution here is to code an app on a mac server (I guess mac mini as server will become more popular with CloudKit) that add a new Daily CKRecord every day.
Subscriptions
Subscriptions concept is that the client registers for specific updates. You can create a record type called Daily for instance and make users register to it. You should check the Apple documentation and WWDC14 videos (even if Subscriptions are not detailed, it's a good start point).
The good thing is push notifications are linked with the subscription concept. So basically you say: Send my a notification for each new CKRecord of type Daily added.
BaaS party
What is the point for using CloudKit (vs Parse and other?)
Price: CloudKit has a really nice pricing
Ready to go: 2 clicks inside XCode and you are ready to go
User consistency: you get free user login for all his devices through their iCloud account. With a very good privacy system. And you can get relationships with a smart system.
But:
You are stick on Apple platform. We don't even know if we could export the data..
Only data-centered for now (no server-side code)
The CloudKit dashboard is too limited
The future
CloudKit is still pretty new. At the WWDC some guys behind it made me understand that they are still heavily working on it. My bets are they are working on 2 important points :
Server side code execution through remote scheduled tasks
CloudKit for Analytics (Visualization side)
Edit: Apple guys are fully aware and concerned about the lack of web access for the data. It means that one day it may be accessible from other platforms. I read in a comment that Apple probably would have bought Parse if CloudKit wasn't better, AFAIK they tried to buy Parse (skills buy it's said, but we don't really know).
Update WWDC15
CloudKit is now available in JS and some dashboard are available now. Wait and see.
Update February 2016
CloudKit Now Supports Server-to-Server Web Service Requests
Web Services Reference
In some cases, we do not need server-side logic, and just storing static data can cover all the usage scenario.
In this case, it would be very helpful if there's a free accessible storage that you can store something. CloudKit provides such stuffs rather then full service platform.
Yes it is limited. Anyway can be useful for some people. For example, your case actually can be supported CloudKit. Though CloudKit is just a static storage, it support subscription. Which monitors a set of conditions and pushes the event notification to client. It's fortunate that the only background job feature supported by CloudKit is just what you need.
Anyway, if you need more, then you might need to consider full fledged servers. Usually simple web services with simple server-side code execution support are also limited.
You cannot upload any code to run on Apple's servers?
You can and you can't. You can't upload code / SOAP based web services to the server, instead of it you can upload / store observers on the server, called subscription.
whole thing pretty limited and not really comparable?
I would say in CloudKit and in MBaas client communicates with server though a more narrower more robust interface: you can not upload exotic web service to do XML parsing, database manipulations and based on it trigger push notifications, but RestFull architecture allows you to perform the 4 basic operation on the data store, and with subscription client can get notified about INSERT / UPDATE / DELETE operations performed on tables.
I think MBaas is just the next step in evolution of server - client architecture. First it seems it is limiting, but you can do all as in SOAP based web services world. Development is extremely fast / scalable / comfortable to use and easier to control things like permissions / setup, maintain server, security needs almost no effort.
Believe it or not, you can actually get REALLY far with this approach.
I've not used CloudKit, but I can describe for you my application stack:
AngularJS (or your favorite client side HTML rendering framework): A single page will host a series of templates/controllers selected by the router and driven by users changing the anchor to select which page they're on.
Firebase.io (or your favorite cloud storage): Any dynamic data goes into the cloud document store. The controller needs to load the data and render the template on the client, and when the data changes, send the data back. This also provides the authentication and authorization as well, since you can limit access to the data.
Now you need a place to serve the HTML/CSS/JS/images... which requires no 'server side code execution', just a web server where you can put the assets.
Using this technique you could store all the user's topics in the database for that user, and when the page loads, go and aggregate all the sources for those topics (also stored in the database) completely client side. There's nothing in your example application which actually requires server side execution that I can see, so long as you have cloud storage which will provide you with authentication and authorization services, and a 'dumb' web server for serving up static assets.
CloudKit isn't a full-fledged web hosting service. Instead, it's an SDK for iCloud. You shouldn't be putting a web site up there, just storing user data that you may want to use in multiple applications or platforms.
iCloud APIs enable your apps to store app data in iCloud, keeping your apps up to date automatically. Use iCloud to give your users a consistent and seamless experience across iCloud-enabled devices.

How to update iOS SQLite database from website form?

I have been working on iOS application for sometime, and I am using Core Data to manage the SQLite database for the application. The users of the application can update the data associated with their account using the application, but I would like to create a simple web form where users could update certain information asosciated with their account. Basically I would like a user to be able to access a web adress from their personal smartphone or computer, login, then update information asociated with the account stored on the iOS device. What are the possible solutions I could use to accomplish this?
Breaking down your question:
Currently you have an iOS app which uses a local SQLite DB to store data
You want to let users update information in this DB remotely (i.e, via a web site)
Unfortunately to do this you're going to need to make some significant changes to how your app works. This is because it's impractical - if not nearly impossible - to do this kind of thing and keep the database local to your device.
The standard way of achieving this would be to store your database remotely on a web server, and then have both your app and your web form interact with this server to retrieve and update data.
There are lots of different ways to do this. Fundamentally, you'll need a server running a database, and a web service to access it. You could implement this yourself, using something like MySQL or PostgreSQL, along with a language of your choosing (Ruby, PHP, Node, etc). Another option is to use one of several 'backend as a service' providers. These are companies that provide 'out of the box' backend functionality for mobile apps. Two popular providers are Parse (owned by Facebook) and Stackmob.
Whether you choose to do it yourself or use a backend provider will depend on how confident you are. It's not an especially hard or tricky thing to put together on your own, but there are several common pitfalls you're likely to encounter.

How to create a server accessible by an iphone app

I a thinking of creating an iPhone/iOS app that would include a feature where one user could create a list of words and then save them to their account on a server. Also (and this is very important), the user could share their list with other users by giving them permission.
So my question is, how can I go about creating such a server? For right now, I have a home computer (running Windows XP that just stores data for my music system) which I can use to host the server. I am also open to the use of other online storage services like Google Drive or Dropbox (I can't remember if Amazon does anything like that). However (and I know this may complicate things a bit), but at least for now, I want/need to stick with free services/options.
Just to recap, the key features that I am looking for are:
create users/accounts (on the server)
eventually I may [try] to incorporate the use of other services to log users in like with their email account, OpenId, etc.
the ability to access (log in to) the server (with credentials) from my app
the ability to send/receive data between the server and my app
the ability to share data between users
I know this is a lot to ask for, but if anyone has any suggestions or can get me going in the right direction, it would be much appreciated.
The basic setup would be as follows:
Backend: Database (MySQL), Web server (Apache), with server side scripting (PHP).
Client: iOS device with developed app.
Communication: use HTTP client/server model, communicating with something like JSON.
This is much the same setup as a web server, but instead of serving html/css/javascript etc the results will be JSON.
As far as implementing specifics such as login in, and sharing data between users, this is purely dependent on your implementation. This is not trivial, and not something that can be easily stated in a single post.
Hope this helps.
You could build your own webservice in PHP, Ruby or Python. If you do so I would recommend building a RESTful webservice (http://en.wikipedia.org/wiki/Representational_state_transfer) and then use RestKit (http://restkit.org/) to handle the data in the iOS app. Especially RestKit's CoreData integration is nice in my opinion.
Another solution would be using a service like Parse (https://parse.com/products/data). The first million or so requests per month are free but after that it could get pricy. I personally have not tried it so I couldn't tell you if it is any good.

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