I decided to give CyanogenMod 12 (= free version of Android 5) a try. Studying occured! I had to figure out how to install ClockWorkMod ROM-manager. After that it was easy to transfer CyanogenMod 12 as a zip-package from Ubuntu Linux to Nexus 7 via USB-cable.
CyanogenMod 12 feels so quick! Much quicker than Android 5! There is an additional Google-apps-package available. I don't want to install it! All I need is a web browser which is able to enter the services I need; Facebook, Twitter, Gmail, news sites. I try to avoid additional apps and don't want to download apps from Google Play -store.
I wonder how long my Nexus 7 will be supported in the future? Will CyanogenMod 13 ever become available for Nexus 7? Is Microsoft really going to purchase CyanogenMod? Tricky!
It's not an android?