The size for an Expo app on iOS is approximately 33mb (download), and Android is about 20mb. This is because Expo includes a bunch of APIs regardless of whether or not you are using them – this lets you push over the air updates to use new APIs, but comes at the cost of binary size.
Read moreHow do I reduce the size of the Expo app?
If you want to upload it in play store then it much better that you run expo build:android -t app-bundle and upload it . At play store bundle reduce their size approx. 30-40% of its actual size. If you want to run build directly to your android without uploading play store then you need to run expo build:android -t apk.
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