On APK Cart, you just need to tap on the upload button and select the APK file you want to upload. After that, it will ask you to either delete the file after sometime or not. If you want delect just select the time, otherwise select don't auto delete. Now tap, upload and it will start to upload the file. After that, It will give you direct download link. If you want to have a history of your files and want to access them anytime, then just make an account.