Google trims the size of app updates with new data-saving technique


With millions of apps in the Play Store and enough space on our phones to comfortably store hundreds of them, updating can be a tedious, data-chomping process. Earlier this year, Google announced it was using a new Delta algorithm that reduced the size of updates by as much as half when compared to the old way of downloading APKs. Now it’s taking it a bit further in a continued push to save you time, space, and money.

The new approach, called file-by-file patching, creates updates that are as much as 90 percent smaller than the full app. On average, the process trims download size by 65 percent, saving users some 6 petabytes of cumulative data each day, according to Google’s estimates. As Andrew Hayden, software engineer on Google Play, explains in a post on the Android Developers Blog:

Imagine you are an author of a book about to be published, and wish to change a single sentence—it’s much easier to tell the editor which sentence to change and what to change, rather than send an entirely new book. In the same way, patches are much smaller and much faster to download than the entire APK.

Google Play Store file patching
Google has seen some tremendous results with the new file-by-file patching technique.

As he goes on to explain in more technical detail, file-by-file patching is based on detecting changes in the uncompressed data of the new and old files, comparing the two to determine they are a perfect match, and finally recompressing the data back to the original size. He notes that processing power is an issue, so the technique may actually take longer on some older devices. Consequently, Google is limiting file-by-file patching to auto updates for the time being to ensure users won’t be adversely affected.

Why this matters: Data overages are an increasing concern as we turn to our phones to do more and more throughout the day, so any amount that can be saved is certainly welcome. While many users undoubtedly opt to perform auto updates over Wi-Fi anyway, file-by-file patching is an exciting look at how Google will one day be able to keep our phones up to date wherever we are without it eating away at our data plans or remaining storage