Google Map Zoom Invert is an Xposed module that inverts the one-finger zoom gesture in the Google Maps Android app.
The Google Maps Android app contains a single-finger zoom gesture: double tap on the map, then slide your finger up or down to zoom. I find this gesture quite handy, so I was quite surprised when a Maps update that rolled out a few months ago inverted the gesture without warning. Now you swipe up to zoom out and down to zoom in. This behavior is frustrating to me not only because I'm used to the old behavior, but because it now behaves opposite of the desktop version of Maps! Scrolling up zooms in on the desktop, but swiping up zooms out on Android.
This module, once installed, will intercept the single-finger zoom gesture in Google Maps and invert it, restoring the old behavior: swipe up to zoom in, swipe down to zoom out.
This module has been tested using Maps 7.5 with CM 10.2 on the Galaxy Nexus and first generation Nexus 7. I imagine it will work on all devices so long as you have a reasonably current version of Maps.
Note that if you have a version of Maps below 7.4, you already have the "old" zoom behavior, so installing this will probably invert the zoom and you'll have the "new" behavior! But I've not tested this.
The code used to build this module can be browsed or checked out from https://hg.bgreco.net/gmapzoominvert/.
If you're interested in how this module works, take a look at GMapZoomInvert.java.
Discussion for this module can be found in its thread over at XDA Developers.
Many thanks to rovo89, for creating the Xposed framework that makes this module possible.