Android's 24 hour sideloading wall

I was showing a friend the Pokémon gen1recomp project on my phone the other day, and he wanted it on his. Easy enough. Hand over the APK and the files it needs, walk him through the setup, ten minutes while we’re sat in the same room. Except his Pixel 10, running Android 17, wouldn’t have it. Install blocked, unverified developer. The way through is to enable developer mode, confirm nobody is coercing you, restart the phone, wait a day, then come back and authenticate again. A day. He was travelling to the other end of the country the next morning. Whatever momentum we had was gone. It’ll happen over WhatsApp in a week, or it won’t happen at all. My money’s on won’t. This is Google’s advanced flow, the install path for any app whose developer hasn’t registered an identity with them, and it went live everywhere in August. Not only in the pilot countries, not next year. It’s on UK phones now, and staying on an older release won’t help, because the component doing the checking ships…