great!
did you use any extension? If yes, then please credit the extension developer...
see also
Why it’s a good idea to give credit by Corey Wainwright.
Taifun
Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by 
Taifun.
Thanks for your kind suggestion ! I have given him the credit for this extension.
you forgot the link to the extension page...
also do you still plan to charge 20 USD for a simple test project, which just uses a few blocks? What about providing it here for free including a screenshot of the blocks?
Taifun
and as you have been previously advised:
What guarantee is there this will work correctly? If it doesn’t work and the user loses money will you be responsible for compensating the user?
All Developers should use their very best effort and resources to produce the best possible code for their App. As you know, there can always be something unintentionally overlooked or changed by another party, and thus it is wise to ask the user to accept a disclaimer before using the App if a failure could lead to a dangerous situation or have other undesirable consequences.
The developer of the extension does not state how his/her code works - it could be as simple as counting the number of digits, which is not an adequate check.
Aquib - you are still breaching forum [App Show Case] rules by asking for payment and by offering an APK. If you continue down this path we would have no choice but to expel you from the forum, something we are reluctant to do because of your enthusiasm but nevertheless you have been warned.
As I have already informed you, there are a number of stores you can use to sell your APKs. However you must perform due diligence by Beta testing your App on as many devices as possible using Beta Testers (can be friends, family etc - people who would use the type of App you have made).
https://www.professorcad.co.uk/appinventortips#TipsAppStores Alternative Stores you can upload your App to, in addition to/other than Google Play.
Only credit card number is required. No other details are required.
And any data is not stored. And I tested this app on mobile. Its working fine.
@ChrisWard I have noticed some people on the community using paid option which encouraged me to do that.
Saying that, if any rule is breached then i will definitely remove the paid tag to free tag.
That would be in the Extensions Forum, not here, and not APKs.
if you are selling aia then give the aia without extension because it will look you are reselling someone's extension
How extensive were your tests?
- All tests performed with real card numbers?
- Did you deliberately make fake numbers with the correct number of digits?
- Tests with incorrect number of digits?
- Tests including space characters, dash characters etc?
- How many tests?
Validate credit card was always a good programming exercise. I have added it to the mathematical code proposals.
Yes to all.
15 to 20 times.
Here is my free card verification app, without extension.
@Aquib_Khan I think your project should be free because it's easy to make
If you want to make a paid project, I suggest that the project is difficult to make