Imagine if Ford remotely disabled the engine on your new F-150 pickup because you chose to have the door locks fixed at a corner garage rather than a dealership. Sound absurd? Not if you're Apple.

Since 2014, the world's most profitable smartphone company has — without warning — permanently disabled some iPhones that had their home buttons replaced by repair shops in the course of fixing a shattered screen. Phones that underwent the same repair at Apple service centers, meanwhile, have continued working just fine.

The message seems clear, at least to the multibillion-dollar independent repair industry: Your phone is yours until you decide to get it fixed. Then it's Apple's.