why does an app update need more space

[AC Question]

16 gb card not enough space apps update ,not enough space now ?why does an app update need more space if it is replacing old data,keep running out of space on my android tablet

 

[Lawson Denny]

I believe that the update is installed then the old version is uninstalled. So if that is right, that would mean the app is basically there twice until the old app is deleted. So say that you are updating Google+. The app is 29.58 MB. So when you install the app, that is being downloaded onto the phone. Therefore, there is two versions. Altogether equaling 59.16 MB.