Please note that this article was written in early 2017. The newer Lexar 633X cards manufactured in 2017, no longer work with the Thinkware F770/F800.
Officially the Thinkware F770 is only rated up to 64GB and works well with a decent variety of 64GB cards even from aftermarket manufacturers such as Lexar, Samsung, and Transcend. Because this camera does record at a high bitrate and resolution, it's understandable that customers want to run larger capacity micro SD cards. However, unfortunately the Thinkware F770 is not rated up to 128GB and Thinkware themselves do not manufacture a 128GB card for use in their dash cams at this moment.
That being said, a few customers and even ourselves have reported success running 128GB cards on the Thinkware F770 with cards like the Lexar 633X and Samsung EVO+ 128GB. Unfortunately, with the latest batch of Lexar 633X and Samsung EVO+ we've seen issues across the board. There's been some changes with the manufacturing that have affected their compatibility with the F770. At the moment there are no aftermarket 128GB cards that seem to consistently work with this camera so they aren't recommended, and dash cam users should only experiment at their own risk.
One thing we really like about the Thinkware F770 is that the camera will alert you right away if it doesn't like the card you put in. The message "memory card error, system restarting" will repeat until you put in a memory card that is compatible with this camera.