I do lots of testing of apps in real phones, not emulators.
The thing is that the phones must be connected to the PC all day. Because of this, phones battery get swollen and I have to buy phones regularly.
Do you know any android phone which can be connected and on all day all week without getting swollen after a time?
Must be real phones, emulators are descarted.
Get a fairphone and remove the battery. As long as the phone is connected to the PC and is getting electricity, it will work without a battery like PCs.
“testing of apps”.
You can use wireless ADB, or try to set the battery limit to 80% and only set charging to only start below 30%. Wireless ADB settings can be found in the developer options. battery options don’t always include the option to require battery level to drop below X% before charging starts again, and if it is, it is usually branded as battery saver feature or smth like that.