Android makers really want to make their phones eye-catching

Samsung, for instance, hopes to encourage upgrades by giving its new Galaxy Note 7 phone an eye scanner for identification and related security features.

Motorola offers mix-and-match modules that let you upgrade your phone on the fly, while Alcatel is focused on adding virtual-reality features, including a headset.

In the Note 7, Samsung takes the notion of such "biometric" security a step further, adding an iris scanner that detects patterns in your eyes to confirm your identity.

With the Note 7, the iris or fingerprint can also unlock a secure folder where you can stash sensitive photos, documents and email accounts you might want to keep away from friends who borrow your phone to look at baby pictures.

Samsung also brings water resistance and its excellent Galaxy S7 camera to the jumbo Note 7, while offering easier access to camera settings using swipes.

LG introduced an earlier modular design with its G5 phone in April, although that phone forces you to shut it down every time you replace a module.

[...] many phone cases and other accessories offer similar functionality, but they aren't as fun as what the company calls Moto Mods.

For now, it lets you swap batteries and attach a camera grip with physical buttons to take shots and control video recording.

Unfortunately, Alcatel's innovation might feel obsolete in just a few months, when Google releases its Daydream system for headsets and phones.