iPhone out of space and won't sync

I couldn’t sync my new iPhone photos after trying several times. Finally on the iPhone I got a message (which I can’t seem to find again) about Mylio not having enough room. The phone has only 8GB available and Mylio is using 112 GB out of 256 GB (got the largest available just for photos). Presumably what shows as photos is in iOS Photos. Mylio is the largest with a mapping application placing a distant second at 35 GB.

Do I have to delete Mylio from my phone and start over again for the iPhone?

This could also be a Feature Request for auto-resizing of the Mylio library.

If you have other devices on your Mylio account that are storing the full-size original versions of your photos, you can adjust the device sync quality policy on the iPhone to store the “optimized” versions of your photos and free up space:

You can find this on the Dashboard (on mobile this is the little icon that looks like a phone in the top-right) > Devices > [Your iPhone] > Device Quality > Auto Optimized.

You can also clear the cache (Troubleshooting: What is Cache and How Do I Clear It? - Mylio Support) and/or adjust the Minimum Free Space under “Devices Storage” on the device settings window.