My phone (zte maven 2 and I also believe it is called a z831) only has 8 gb of storage and I ran out of room so I added a micro SD card yet my phone still complains about having no storage and I still cannot download anything.
For this model, there is no option to use adoptive storage. In other words, you cannot format the sd card into internal memory. To gain internal memory so you can install more apps, the best you can do is to move all your data (photo, video, music) to the sd card. There might be a very few apps that can be moved to sd card. But the gain is so little to be worthwhile. With all the bloatware that came with the provider, the usefulness of 8 gb of internal memory is really limited.
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