Discrepancy between sizes of apps listed in Play Store vs. actual installed app size The Play Store lists the size of all apps available in their store.  When a user downloads and installs apps, the actual sizes reported by Android are often larger than the sizes listed by the Play Store.

Of importance, this discrepancy occurs before applications are even run for the first time.

What is the reason for the discrepancy?
Apk and zip files are essentially the same, compressed. Before the system can use the file it needs to decompressed. So the file is one size when downloaded and another size when installed.

Also note sometimes when apk's are installed, after being opened some data may need to be downloaded. So file size file will increase again.

Differences in size are noticeable when comparing between Android markets, one shows one size and play store shows completely different size.