1. No Root
2. No Bootlocker unlock
3. No Custom ROM
4. Needs Google Play Service
5. Needs to be installed via Google PLay Store
6. Needs my phone number
7. Needs that SIM in that phone
8. Needs that SIM in that slot
9. Needs location
10. Works only via Mobile Data
11. Developer options disabled
12. Needs someother app to be uninstalled
13. Disable VPN (Firewall apps use that)

So for bank stuff to need a seperate phone, other for whatsapp (and other spyware) and then your main thing. And when you go out people ask questions.

I don't understand my apps are developed with their security dependent of the OS, why can't they make secure apps