How to get the current connection wifi channel (frequency) in iOS? - ios

I want to know how to get WIFI channel and frequency information in iOS.
It would be better not to get from the private APIs (because I need to submit it to the iTunes Store).

There's no way to do this using publicly available APIs, as of iOS 7. The OS algorithm controls networking and decides which channel to use based on congestion, interference, and other factors.
If you're okay with using private APIs, then you can use Stumbler, a library that exposes the data you're interested in: https://code.google.com/p/iphone-wireless/wiki/Stumbler
Warning: If you want to use private APIs, then you won't be able to distribute through the App Store (and you'll have all the other hazards that come with using Apple's private API: the banhammer, breakage at any time, et cetera).

As others noted there is no way to get wi-fi frequency on iOS using official APIs.
There is one work-around to determine whether user is connected to 2.4Ghz or 5Ghz range by actively running a wifi measurement. You can set a limit which will not be realistic on 2.4Ghz (e.g. typically speeds over 100 Mbit on wi-fi are not achievable on 2.4 Ghz).
To run wi-fi measurement its better to run true wi-fi speed measurement and not internet speed measurement as the latter can be slowed down by the ISP (and not the wi-fi).
Here is relevant Stackoverflow comment how to measure wi-fi speed - iOS Get Link Speed (Router Speed Test)
In either way you will not be able to determine actual wifi channel, only whether its 2.4 or 5Ghz. This can be further complicated in the future with 6Ghz ranges where it will not be that easy to split between 5 and 6 Ghz.

Related

Which cellular networks stop data when taking phone calls?

We are developing a mobile application that tracks users while they are picking up and delivering commodities. We have overcome many issues, including poor connectivity in rural areas, the app going into the background, and so on.
One issue continues to befuddle us. When receiving calls some drivers lose connectivity, other drivers will gain connectivity, and others (most) have no change in connectivity.
I remember earlier that Verizon iPhone users couldn't access data while on a call. Naively I thought that this issue was completely overcome, but perhaps it is not.
My understanding is that a) there are still some cellular protocols that cannot handle voice and data and b) there are (or were) some settings in mobile phones that give the user a choice.
I have searched for some list of cellular protocols and iOS and Android settings but so far come up empty.
Any guidance would be greatly appreciated.
Hopefully this will provide some more clarity; it all depends on the Radio Access Network (RAN) technology they're using (2G/3G/4G) and the terminal itself's capabilities.
There's 3 umbrella terms of technologies, each with their own revisions and variants, but this should cover it:
LTE (4G) only supports voice calls via VoLTE (Voice over LTE). Calls made over VoLTE will allow the user to continue accessing data at the same time. Many devices & some networks don't yet have VoLTE capability, so they use Circuit Switched Fall Back (CSFB) to drop to a 2G/3G Radio Access Network for making voice calls. (If your terminal does this you then have that RAN's ability to allow simultaneous voice/data.)
3G - There's a few flavors of "3G", depending on the terminal and the RAN variant (UMTS / EDGE / CDMA / HSDPA / HSDPA+) you may be able to access data and be on a call at the same time.
GSM (2G) does not have this functionality, the handset is either in Circuit Switched (Voice) or Packet Switched (Data) mode but not both.
The decision of which RAN to use is based off the priorities stored in the SIM/USIM, the received signal strength of the available networks and the capabilities of the terminal.
This means for example your users who may gain connectivity may find themselves using a 3G access technology on a 4G enabled terminal, with VoLTE support, jumping up to VoLTE to make the call. (Some operators resell to MVNOs but default to slower / older RAN technology like the 3G family)
Others may loose connectivity as you've seen, if they're happily using LTE on a device with no VoLTE support and need to drop to 2G/3G for a call (CSFB) they may loose data services as they're back to the limitations of these older RAN technologies.

Looking for GPS device with on-board RTK that is easy to interface to from an iOS App

I've been researching a possible iOS-based app, developed in Unity, that would require a high-degree of positional accuracy (centimeters).
I expect I would need to connect, from the app, to an external GPS device using Bluetooth (or similar) and obtain NMEA sentences (or similar) containing location data.
My research has brought me to RTK, which is extremely accurate. From what I've seen already, it seems that normally GPS receivers which offer this operate themselves at normal GPS precision (2-2.5m). The correction to a high-accuracy location happens in software on a connected computer or tablet with a connection to an NTRIP server.
Assuming what I've said is correct, does anyone know of a GPS device that performs this RTK correction on the GPS device itself? Ideally I could just connect with Bluetooth or similar and get NMEA (or equivalent) data with high-accuracy location.
It may also be that I'm thinking about this incorrectly. On iOS, assuming there is an 3rd party app performing the RTK calculations, is there a standard way to obtain that high-accuracy location? Alternatively, are there GPS vendors that supply SDKs that would allow me to get to where I need to go?
Thanks very much,
Kieran
There is a recent module from U-Blox named ZED-F9P which has internal processing and is faster then RTKLib. Check this blog for performance
You can buy a board like ArduSimple's simpleRTK2B with an XBee module for WiFi/Blutooth or something similar from Sparkfun. You could also wait for the development board from U-Blox which is not yet available.

is it possible to get signal strength and channels of a wifi?

for Android, several apps exist that show such information, like https://play.google.com/store/apps/details?id=com.farproc.wifi.analyzer does it:
I need similar functionality in my iOS app but can't find any information about that. It this forbidden by Apple?
Apple doesn't allow apps to access the hardware like that. A fairly common workaround is to measure network throughput instead. You could take periodic samples of the current network speed, and then display that data over time.
Network Multimeter, for example, is an app that will give you info on your network as you walk around. It does that by sending data across the network and displaying the throughput.

iOS approach to location based peer to peer communication

I recently have been very interested in developing iOS apps (for iPhone specifically) that can "communicate" with nearby (geographically) apps.
My networking skills/resources are limited, so I was really hoping to make it a peer to peer app, avoiding the need to host my own server.
It seems like I have a few options, including the newish Multi-peer Connectivity framework, and Location services.
I was hoping someone who has experience writing peer to peer apps could direct me to what they think the most logical approach would be.
Additonal info:
*I am only looking to send text/small pictures (speed is not a priority)
*Detecting nearby (within a mile or so) geographically is the main goal
*Possibly communicate with Android devices (I know multi-peer connectivity lacks this)
Peer-to-peer communication is limited to a range of about 50 meters. To extend the range you can create a mesh using intermediate peers to relay messages. That is how the Firechat app works.
If you want to communicate over greater distances without a mesh I believe you will need to go via the cloud
In terms of communicating with Android, the people who made FireChat are coming out with their SDK. Not sure how/what pricing will be but I assume they will offer this cross platform function. There are of course other ways but I am not that advanced in app development to know them yet.
For a simple chat app there are many free online tutorials that help you create iphone to iphone chat app that can also send images. Range will be limited however to whatever is max for WiFi. Like Keith said, mesh is another option but I believe everyone in the network has to have the app for the data to bounce.

Access 30-Pin connector with code

I am trying to set one pin of the old iPhone 30-Pin Connect from low to high so the best would be from 0V to 3,3V. Is that possible with a simple PodBreakout board like this?
https://www.sparkfun.com/products/8295
If not can you send a constant voltage out of the iPhones audio jack (This could be a good method too, cause now apple used its 9-Pin Lightning Connector).
I already searched the web, some say you have to jailbreak your iDevice, some say you need an authentication Chip, and some say it works flawlessly without an authentication chip, but I cant find any help online.
Thanks
You can't "send a constant voltage" out of the audio jack. There is a series capacitor there that filters out DC and very low frequency signal components.
To get proper help on this you can apply for the MFi program. I think it's free for educational purposes. It's under 100$ for sure. There is an NDA involved.
If you want to avoid the MFi you can always use BLE to communicate with periphery.
Or try to implement software FSK (or DTMF) modem on one side and a hardware one on the other side (using the audio lines).
Since it seems you simply want so see a binary (on/off) signal - you could generate a fixed pitch tone in the app (2kHz for example) and use a narrow-band filter on the hardware side (audio-jack connection).
Or maybe (to make sure your app is present on the other side a 2kHz tone would mean 0 and a 4kHz tone could stand for 1.
The authentication chip (and an MFi license)) you are talking about is needed when you try to communicate with the iOs device:
via BT (excluding BLE)
via USB (30 pin connector or lighting connector)
via UART (30 pin connector or lighting connector)

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