Android app install size 2-3 times size of Apk, and Apk more than twice as big as size in Editor.Log

Edit: Sorry about formatting. The website seems to be broken atm. Complete build size is 7.3 MB in Editor.Log Checking the apk, the size is 21.9 MB Checking the size after installation the size is 19.06 MB in "Application" and a whopping 41.88 MB in SD Card App. I didn't move it to the sd card manually, so I'm guessing it does that automatically. If I manually move it to device storage, I get 40.05 Why is there such a big discrepancy in numbers? Why is the install so large compared to my game data? For reference here's a break down from Editor.Log Textures 287.5 kb 3.8% Meshes 0.0 kb 0.0% Animations 13.9 kb 0.2% Sounds 2.3 mb 31.6% Shaders 4.7 kb 0.1% Other Assets 112.8 kb 1.5% Levels 146.9 kb 2.0% Scripts 518.6 kb 6.9% Included DLLs 3.9 mb 53.8% File headers 16.7 kb 0.2% Complete size 7.3 mb 100.0%