The options for increasing the space

There are several options to increase the space of the root partitions. Currently available options are:

1.  Use the space from a unused partition  (Not on Xperia X). This option has the drawback that if you want to reflash your device with SailfishOS, the flashing won't work, you need to restore the partition first, e.g. by flashing Android.
2.  Shrink the home partition and add this space to the root partition. This means you have less space available on the user parition afterwards.
3. Configure an SD-card to extend your root partition. Your SD-Card has to be inserted all the time for the device to work.