Estimates the size of Google Play patches and the new gzipped APK. From two APKs it estimates the size of the new patches as well as the size of the gzipped version of the new APK, which would be used in cases where the patches are unexpectedly large, unavailable, or unsuitable. Google Play uses multiple techniques to generate patches and generally picks the best match for the device. The best match is usually, but not always, the smallest patch file produced. The numbers that this script produces are ESTIMATES that can be used to characterize the impact of arbitrary changes to APKs. There is NO GUARANTEE that this tool produces the same patches or patch sizes that Google Play generates, stores or transmits, and the actual implementation within Google Play may change at any time, without notice.