Phone gives warning when installing downloaded apk files

[chjcatoj]

Sorry for my disturbance. I have just used Z3 for a short time and There's some problem I don't know.Plz help me!

1. Every time I download the APK file, my mobile reports: This file may harm your device …..then I dare not load the app anymore. There are many interesting applications that Google Play doesn’t have , such as Google Earth ...

2. I don't know why whenever I receive my incoming calls or make a phone call, Z3's screen light goes off. I try to touch every point but it's no use. Sometimes, I want to turn on loud speaker but i can't. This irritates me a lot.

Please give me some solutions. Thank you in advance!

[_alexdon_]

For 1, if you download from different locations (not play store), you will get that message as the apk is not verified.

For 2, do you have a screen protector applied that might cover the proximity sensor? Also, any chance you can clean up the part of the screen where the sensor is located?

[rockieland]

whenever you download third party stores, these alerts appear. Some stores contain malwares but some don't. I think this instruction will help you: http://computer.howstuffworks.com/know-if-app-safe1.htm

I only trust Amazon App Store and http://choilieng.com. They're free of malware.

[Lotusbeauty]

Yeah I agree, I download APK from it and it's really helps. 

This also helps