What does it mean to be a beta tester? Do you try out future features earlier or something? Or is it meaningless at this point in iMtG's life? Also, what does the stuff in the pre-made email to Piotr mean?
Being a Beta Tester does give us the choice of sampling future elements of iMtG but it's not as simple as that. We often have have buggier experience but it's this that helps Piotr make a better app for the rest of the public. The more statistics he has, the better service he can provide. So apply and have a go but be warned, it's not always awesome. 😊
So in the application email, what does it mean to register my device at that weird address? Does this affect me, or is this just some code that only Piotr understands?
The weird address is TestFlight, a platform which we use for BETA distribution.
And it's harmless to your device.