After creating and testing an app, the next process is to package the app by creating an *apk (Android) that is loaded on a device directly (side-loaded) or through an app store.
The apk is an zip archive of compressed files and folder in the DEX code format:
There are various channels in which you can distribute your app. Google and Apple makes up the lion's share of apps that are submitted so they will be discussed the most.
The Google Play Store is the easiest app store to deploy to for Android devices. Apps are scanned for malware and now has a human review process like Apple iOS apps to ensure an app does not do adverse things to an Android device. However, its content is not filter. There is also a faster turn around time when the app is submit and when it appears in the app store, typically within a few hours.
An Android app is confined to a sandbox which means that only certain areas (e.g., storage) can be accessed by means of permissions that the developer registers. A new feature call Verify Apps compares an app to a large database of known malware. If there is a match, a user is given a warning and has the opportunity to cancel the installation.
Before you release an app to the public, you can optional use Google alpha and beta testing channels with either a closed or open testing system. In a closed system, you specify email addressses of the people you want to use test your app. In a open system, the app is published and can be found and installed by anyone from the app store. It will be labeled with "Unleased" along with the name of the app and with a note that states, "This is an unreleased app, it may be unstable."
The Amazon App Store is primarily designed to serve apps for Kindle Fire devices. To search for an app, select Apps and Games from the search drop down menu and then type an app name and click the Enter key. However, other users can get an app through the Amazon Appstore by downloading it.
Besides the two stores mentioned above, there are other app stores you can use to submit your apps:
There are many other stores which focused on particular regions (e.g., Asia and Africa). However, submitting to them all manually can be a very time. There are services that willl let you submit ONCE and publish in MANY app stores. CodeNGo will let you publish one app a year for free to over 30 stores including Amazon, Google Play, Aptoide, etc.