Unfortunately, we do not currently have an API to print orders. There are two options currently available:
1) Build your own Android app to handle printing and go through our app approval process. Since you already have an app for online ordering you would probably want to modify that app's configuration to also be an on device app so you would only have to get one app approved. There are some complexities here, see Jeff's answer here - https://community.clover.com/questions/24117/some-times-all-line-items-not-getting-from-order-u.html.
2) Have your merchant install and use a third party application in our app market. This one seems like an option - https://www.clover.com/appmarket/apps/25BCJ2KGEJNEC. However, I haven't personally used it so I can't endorse it or say it for sure meets your needs.
We understand this is a pain point and has been for some time. We are working on a new set of APIs that will be easier to work with and expose this functionality but I am guessing they won't be released for quite some time so I cannot recommend that you wait for them at this point.
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