As this is your first post, welcome to the community! You are talking to your fellow customers, not directly to Pure Planet.
Pure Planet are very clear that the key feature of the way things work is by using the app - "You'll need a smartphone or tablet running iOS 9 or above, or Android 5.0 (Lollipop) or above to join us." I find being able to take my phone into the garage to get the reading really helpful, and the built-in torch is great too.
The good news is that you only need to send photos with your first readings.
But if you really find using the app too difficult, I think the only sensible option is to switch again. But I would encourage you to give the app a trial for 2-3 months, and see if you get used to it.
Hope that helps.