Spying frameworks wouldn't be responsible for taking so much space, usually the largest files in mobile apps are the assets (sounds, videos, images, etc.) and not code, code is actually quite minimal.
So yup, your assumption is probably very wrong. And I'm not an Uber user (exactly for privacy and ethical reasons).
Don't iOS apps also have all resources embedded regardless of the device? Like high res retina icons are in the app even though you are using an iPhone 4 or whatever. That would also explain the larger app size.
So yup, your assumption is probably very wrong. And I'm not an Uber user (exactly for privacy and ethical reasons).