Google Play App Signing reduces the size of apps, and makes them more secure

Google Play App Signing, which launches in beta today, automatically adapts apps to fit different screen resolutions, RAM configurations, and processor models. And it compresses apps by eliminating redundant code.

Google said it’s already made a tangible difference. Deliveroo, one of the group of select developers who were given a chance to preview Google Play App Signing, saw its Android app shrink by 36 percent — from 13.6MB before to 9.1MB after. Seven saw a 48 percent reduction in size, from 53.7MB to 28MB.

Google Play App Signing’s security features revolve around private keys, the cryptographic string of characters that app developers use to verify their identities. Private keys distinguish legitimate apps from imposters, but previously, if a developer lost or misplaced their key, they’d have to publish a brand-new app. With Google Play App Signing, that’s no longer necessary.

Now, developers can upload their private keys to Google’s servers. When an app’s uploaded to Google Play, the App Signing service will automatically “sign” — or verify — the app.

The new service is the newest in Google’s ongoing effort to improve the Play Store experience. Over the past two years, Google’s expanded the Play Store to Daydream, its virtual reality platform; Android Wear, its smartwatch operating system; and Chrome OS on laptop computers. And it’s introduced features like Early Access, which lets developers test and provide feedback on beta apps; Indie Corner, which highlights the work of independent developers; and the Google Play Awards.

It’s seen success. Google said that Android users downloaded 82 billion apps from the Google Play store over the past year, and that the number of monthly installs regularly exceeds 1 million. And users are spending more — there’s been a 30 percent uptick in buyers, Google said, and a tenfold increase in the number of monthly subscriptions.