Might want to check again. I’ve been using Llama just fine for years on a Note 4 running Android 6.01. Cell location working fine - much better than GPS or WiFi on battery use.

Note that the first 3 listed are 2.1 A SHARED between the 2 USB ports - not 2.1A per port at the same time. Something like BESTEK® 3-Outlet Wall Mount Mini Travel Charger might be better for true USB power users (4 USB ports - 2 for 2.4A each, 1 for 1A, & 1 at 0-2.4A). Haven’t tried it myself.