This mean, you can’t install any version Gapps zip file on your phone, tablet. Gapps zip files are categorized according to the Android firmware version. But if you factory reset your device it’s not affect to these apps. Otherwise you will lost Google application log-in details on your phone as well as above mentioned Google services. Therefore every time when you’re updating or reinstalling your Android phone, tablet ROM, you have to install this file. This zip file contain files are saved (push) into the System partition. This zip file install using the recovery, when you installed the ROM, after that you have to install the Gapps zip file. You can download them from the Google play store market. But it’s not include Gmail, Map, YouTube etc add-on applications. Gapps zip file have all of these essential Google applications. Without the Google play store app, you can’t access and install any app on your phone (if you don’t have the apk file). As a result of that, after you installed these custom ROM, some of the useful Google services such as Gtalk, sync, calendar, face lock and even the Google Play store app can’t see. Most of the Android open source project (AOSP) based, after market firmware such as CyanogenMod, AOKP, Paranoid Android are release without these application. Google apps also called Gapps is a one of the essential application for the Android devices.
