A customer alerted me to an unfortunate recent development. Apple's Testflight app, which we are using to distribute the Featherweight GPS Tracker App, recently was "upgraded" such that it will no longer be installed on devices that have less than iOS 13. The iPhone 6 only goes up to iOS 12.4. I am running a test iPhone 6 right now on iOS 12 that already had the older version of TestFlight installed, and it's still working, and so is the Featherweight app on that device. But for an iPhone 6 that doesn't already have TestFlight installed, you won't be able to install it to install the FIP, as far as I can tell.
So now the new minimum iPhone if you are getting a used phone to use as a dedicated rocketry tracker is the iPhone 6s, which can run the latest iOS, iOS14. These are available for about $120 on eBay. As always you don't need any cell phone data to use the phone as a tracker, just the bare device.
See the link below for the latest iOS version that is supported for each device.
https://iosref.com/ios
For the iPad, it's the Air 2 or the mini 4. For the ipod touch, it's the gen 7.
So now the new minimum iPhone if you are getting a used phone to use as a dedicated rocketry tracker is the iPhone 6s, which can run the latest iOS, iOS14. These are available for about $120 on eBay. As always you don't need any cell phone data to use the phone as a tracker, just the bare device.
See the link below for the latest iOS version that is supported for each device.
https://iosref.com/ios
For the iPad, it's the Air 2 or the mini 4. For the ipod touch, it's the gen 7.