Super proud to showcase Foqos! I wanted to create a way to physically block apps on my phone, always had a bunch of NFC tags, combined the 2 together over the holiday break and Foqos was born. You can create profiles, write them to NFC tags and track your weekly focus.
Its completely open source and will always be free! There is an affiliate link in the app for nfc tags and donations are completely optional
But i like the idea to make such features accessible to the everyone and not only people who geek out on their phone.
As others pointed out you should implement qr codes which would make it even more usable.