For iOS, as @blasterv said you issue updates via iTunes Connect.
For Android it can be a bit confusing on how to specify the version number properly because you have two numbers to keep track of: versionName and versionCode.
The versionName is a string and can be anything you want. (Like “1.0”, “1.2.6”, “2.0-beta” or even “hocus-pocus” etc).
This string is *not* used to determine if an update is available. It is only used to display the string to the user, like in the Manage Applications section of the Settings app.
The versionCode is what the Android Market uses to determine if an update is available.
This is an integer number and the only requirement when you upload an update is that the new app-version has a versionCode that is higher than the existing version.
Since it’s an integer this means that you can’t have a decimal point to indicate major.minor versions.
What I do to simplify things is to treat this as a release number and increment it by one every time I’m ready to release an update.
An example of my numbering scheme is as follows:
version version
Name Code
"1.0" 100
"1.1" 101
"1.1.1" 102
"1.2-beta" 103
"1.3" 104
"2.0" 200
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