By using the Android App Bundle, Duolingo explained that they were able to reduce their size significantly without sacrificing functionality. Previously, they had used a single APK, and while they investigated using a multi-APK approach, multi-APKs would have required substantial changes in their build scripts to handle version codes and file names. The team would have also needed to re-train their developers for managing releases. App bundles, on the other hand, required almost no changes to their existing automation and were straightforward to generate and upload.
“Transitioning to the Android App Bundle was easy,” commented Bob Meese, Chief Revenue Officer at Duolingo. “The team’s existing automated build script was designed to upload APKs, but all they had to do was add support to upload app bundles. We only had to change a couple lines of code.”
Testing was also a simple process. The Duolingo team used
internal
test tracks, which made distributing the app to employees for testing “seamless” Meese reported. And they found it was easy to roll it out to their existing users, with little work involved on their end.