When you download a large, 100 MB game, it may take a long time and a considerable amount of bandwidth. This can be frustrating for some users who have slow or metered connections. Even more frustrating is when a small bug in one line of code causes the user to have to redownload the entire app.

To help curb this problem, Google announced in 2012 smarter app updates. Instead, Google looks at the parts of the update that are different and only downloads that patch. Then the installation process consists of merging and reinstalling that patch. It’s a great way to reduce the size of downloads by a significant amount.

A recent new algorithm called bsdiff reduces delta sizes even more, making them roughly 50% smaller. That makes a considerable impact when there are a billion users requesting updates from many apps a day.

Using the xdelta algorithm APK expansion files, additional very large files that can be downloaded at runtime to finish obtaining all the necessary resources, 12% of storage was saved on initial download and 65% on later updates.

Google’s now trying to make this more transparent to the user. In the mobile version of the Play Store, and likely the TV version soon enough, app updates will now display the “Update Size” instead of the full download size. It can more clearly illustrate to users what will happen when they select the “Update” option.

The news was announced in this blog post, and the article goes into greater detail about file sizes. Although each update is small, some users will be frustrated by that initial download. There are a few suggestions at the end of how to reduce the size of your app so the initial download is minimized as well.