Limits on silent push notifications per hour - ios

I am trying to understand what is the limit for push notification per hour assuming I do not show the user a message, only update data on a terminated app, to move some small critical calculation from a server to the phone.
So for example if I want to update a device on a value that's being changing all the time, and say I want to inform the phone on a new value every 1-3 minutes , or even 10 minutes, wake up and calculate something and decide if I should alert the user.
Reading many posts like is there a limit when sending push notifications to multiple iOS devices?
did not provide a clear answer.
Is it something popular to inform a device every 10M ? is it a good practice ? do large companies do that ?

It seems that here :
https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/pushing_updates_to_your_app_silently
Apple says you allowed to send 2 Silent Notifications per hour, and it works only when the app is in the background.
When you send real push notification which inform the user on the lock screen, then you can send how many you like (which is pretty strange because both use the same resources from Apple exactly, and on silent notification I even provide better user experience by filtering some of the notification from alerting him, so its not clear why when the user is being alerted you can spam him but when a server update an app in the background - you have a limit )

If you use Remote Notification (silent notification) you have a limit per hour maximum 3 notification you can receive or send.
Silent Notification.
If you want to update your app in background or even if it is killed, without limitation of Push, you can use UNNotificationServiceExtension in order to download something from your serve or you can implement some value to share with your main app, then when user open your app, you can refresh it.

Related

How does Messenger refreshes itself in the background?

How do Messenger and other apps refresh themselves in the background regularly and display every single notification?
Is it a server that sends a signal to the app on a regular basis to refresh their data in the background?
Mostly applications use multiple ways to update notifications:
Send push notification, if in case you want to inform user about the activity.
Send silent push notification, if in case you don’t want to inform user that something happened in background. ( "content-available" : 1 )
IMPORTANT
Background update notifications are not meant as a way to keep your app awake in the background beyond quick refresh operations, nor are they meant for high priority updates. APNs treats background update notifications as low priority and may throttle their delivery altogether if the total number becomes excessive. The actual limits are dynamic and can change based on conditions, but try not to send more than a few notifications per hour.
Source: https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/CreatingtheNotificationPayload.html
But still most apps use this.
Run/schedule a background task to perform some action.

iOS local notifications disabled automatically if app isn't opened

As I see in many apps when setting user notifications as reminders, it works fine but after a while when the user starts to ignore opening the notification or the app it won't send any more notifications.
Is there a way to disable this behavior and continue sending the notifications even if they don't open the app?
What you are describing sounds like local notifications. These are scheduled in code to go off at a specific time. As far as I know there is no such thing as a recurring local notification. They are "simulated" by creating many single local notifications to begin with.
Edit
As PaulW pointed out. Recurring notifications are possible but are rarely used due to their limitations.
When the app is opened it runs some code to create some more local notifications.
If the app is not opened then the code never runs to create the additional notifications.
So, in this example, it is not iOS stopping the recurring notifications because you haven't opened the app. The notifications stop recurring because you don't open the app and give it the opportunity to create more of them.
So, to answer your question. No. The only way to delay this as long as possible is to create notifications that cover a long time into the future. But then I believe there is a limit to the number of scheduled notifications. (A quick google comes up with a limit of 64 scheduled notifications per app).
Edit you could also use repeating notifications but they are limited to repeat every one unit of time. Once a day, once and hour, once a minute, etc... so you can't do it every two hours.
Alternatively you could use a backend to send remote notifications. These could theoretically recur infinitely because the app is not required to create them. Of course, this assumes you have the infrastructure setup to develop this.

iOS Background fetch for local notifications

I have 8 medicine local notifications which differ from day to day.
They work fine for one day but I want to fire them everyday. I used BackgroundFetch to reschedule the local notifications every time fetch is executed. But my problem here is that background fetch depends on how often the user uses the app. What if the user doesn't open the app more often Also I didn't want to implement silent notifications because it will not wake up the app if the user does not have internet connection. what approach should I use instead of background fetch?
EDIT:
I also thought about location updates in background because my notification times are taken from location of user and calculated accordingly. But will this consume a lot of battery?
Since I've got the same issue in an
app that probably does the same stuff as yours, I'd like to share my solution.
It comes with one compromise works only from >=iOS8.
By using an interactive notifications you can reschedule your notifications in background, of course the user need to interact with the notification, but I think that if you different actions instead of open the app or cancel the notification is possible to have more interested user.
It's all about creating a configuration with actions.
Here you can find a tutorial.

local notification at different times everyday

I would like to know what is the best approach to do if I want to fire notifications for more than one time each day everyday.
I did some research and read that notifications for the next day cannot be fired unless the user opens the app the next day and updated the notification. Is that true? is there anyway I can do it without the need of the user opening the app everyday?
Thank you
You can schedule up to 64 local notifications. There is no limit on the time period; you can schedule them years in advance if you like.
That said, if you need some mechanism to schedule new notifications, even if the app is not running at all (e.g. because the user terminated it), you need a background mode for that. Fetch is probably the way to go here, as it doesn't need a special trigger. You could also send silent push notifications in order to wake the app, make the calculations and schedule the new notifications.

Can push notifications be used to run code without notifying user?

I have an app which needs to communicate with a server (to refresh it's data) once every 24 hours. This needs to happen even if the app is not open, nor in the background.
Ideally what I'd like is:
Every 24 hours, my server sends a push notification to iPad
This wakes up the app, and runs the code necessary to refresh the data
The notification is then discarded
Is any of this possible?
Is the app only woken up AFTER the user clicks on the notification? Or can I run some code before showing the notification?
Can I even discard the notification message?
If Push notifications are not the right way to do this, what is???
Thanks guys!
With release of iOS 7 this is finally possible using Remote/Silent notifications. They work same as Push notifications but instead of alerting the user immediately they can fire up background fetch mode and upload/download new content.
Here is simple tutorial:http://www.objc.io/issue-5/multitasking.html
This is only possible if your application is a Newsstand App, if it is, you can send a push notification with content-available: true once every 24 hours.
If it is not a newsstand app, you can instead use GPS fences to run code. It is allowed to let the user set up GPS fences if they want the app to update when the user comes close to an area (ie. their home / work). This will wake the app and you can run the background download then. Instapaper for example does this.
if the period is always going to be 24 hours you can use local notifications instead of push notifications.
your app won't be able to run any code unless the user open the push notification, push notifications are handled by the OS and your app have no control on them while it's not active or in the background you should take a look at the push notification programming guide
an alternative way to accomplish what you are trying to do, is to get the data from the server every time the app is started and the last update happened 24 hrs earlier ,
every time you contact the server save the date in NSUserDefault
every time the user opens the app check if the last server contact happened before 24 hours then refresh data
It is possible using a so called VOIP Push Notification. This notification can run code in the background, even when the app is completely closed.

Resources