That depends on many factors. Among others the number of involved developers, the complexity of the system and what features the client wants. First the app gets developed and then comes the test phase which can take up to 1 year.
We developed the app in a way that makes it very flexible. That means with little work we can reach the same effect as with a brand-new app. This is the result of multiple test runs and customizations to individual needs.
This is a segment that changes very fast. Not only are you investing into the app but also the continuing development behind it as well. If it doesn’t meet your expectations, we make the necessary improvements free of charge.