App not working properly on lower API level but still above minimum

Question

I've been developing an Android App which is targeting API LEVEL 23 and its minimum API LEVEL is 16 . Most of the time I've tested the app on my phone which is running Android 6.0 (API level 23). But I tried it on a friend's phone which is running Android 4.2.2 (API level 17) (I made sure I didn't use anything above that API level). So I thought because it is above the minimum my app requires that everything should've worked properly. However some colors have changed (buttons colors, background color, fonts colors), back button on child activities don't appear, there is a Onclicklistener that doesn't work either.

Is my only solution to recode everything that now is not working properly?

Will changing the compile version do anything?

What other solutions do I have?

Answer 1

Yes, if you took the .apk file from /bin folder (inside the project) that's wrong!!! You have to export and compile importing and cleaning all libs and stuff from that project. Eclipse and Android Studio has a tool for make it automatically

If you are using eclipse 1.-Click right to the project 2.-export 3.-Android (Export Android Application) 4.-select project, create a new keystore (I think u havent one created yet) [if you are going to upload the .apk into play store, dont lose this keystore] 5.-Set your alias, password, validity and name

If you are using Android Studio Google it :p

Answer 2

How did you export the apk? If you take the .apk from /bin folder there will be problems with all devices except with one with you where releasing

Witch theme are you using for that colors? If you use default themes, obviously there will be different colors and forms of every different version (and phone model)

Will changing the compile version do anything? No

Best reguards :)