Except that's exactly how Android phones solved that problem - removable backs. Want a bigger battery? Get one that comes with a bigger back plate, like the Gal

Except that's exactly how Android phones solved that problem - removable backs. Want a bigger battery? Get one that comes with a bigger back plate, like the Galaxy S5 had. Also, before anyone mentions it, you can do this and still have an IP67 rating. Apple has teams of engineers working on marginally different hues of silver/gray. They can spare a few to figure out a case lock mechanism that doesn't detract from aesthetics. For example, you still need a SIM tray, so hide the latch to release the edge in there. They could be crazy and follow the Android phones that use a combo sim and SD card tray to allow Apple users to add more storage, but then they couldn't charge a 500% mark up on 128GB of flash memory. I don't understand people that give Apple a pass on clearly bad decisions that could be remedied by a simple 'Advanced' section in the settings or an almost imperceptible compromise on aesthetics (at least way less perceptible than a monster screen notch or the iTumor case).