I'm not exactly sure about the technical details, but that "can't install on the device" notice is what everyone will see until they send us the email that requests access. The email automatically submits an iPhone-specific identifier that is used to install the application. I think this is what is usually required of testflight, but I could be wrong.

We're all on the 4S, so once we get the email we'll do our best to add you to the testflight list as soon as possible. Sorry for the confusion.

And we've heard from a lot of Android users, and we feel your pain! One of the developers on our project doesn't even own an iPhone so you have someone vouching for you on the inside. It's definitely on our list of to-dos.

Testflight doesn't really work like that - for any app not approved by Apple, you can only open it with your device if the UDID is registered in the build as a tester device.

What testflight does is take your device's UDID (when you register your device with tham ) and allow the developer to rebuild or insert your UDID into the build, and then you can install to your device.

There's still no way (with an unrooted device) to install an unapproved app without the UDID in the build - testflight just greases the path for that process.

As long as you have iOS 5 or later, you should be able to install it. To add to what Daniel said, once you get that error, your UDID (an identifier specific to your iPhone) will get sent via TestFlight to me. I will add your UDID to the distribution profile so that you will be able to access it (you should get a notification at this time). I hope you enjoy it, and since we are very actively developing it, any feedback would be useful for us. We encourage you to send an email to feedback@evertracker.com.