I got a problem already for some time: every time I´m trying to download an app my phone keeps telling me there´s not enough space on it to download it (no matter which app I´m trying to download). Then I started deleting other apps to get some free space but even when I deleted 10 apps I couldn´t download any new one. There´s still around 7 GB data space on the telephone and the internal space is around 50-100 MB (keeps on changing). I set favorite saving space to telephone, but so far nothing worked. Would be amazing if someone could help.
Seems that you have not applied the Unified Partition Upgrade. The link should help you.
You can also search the forum to find out more (little magnifying glass above).
Thanks for the answer. Going to do this, gonna see what happens.