Allow donors to leave an optional tip to Givebutter when making payments through the mobile app, including Tap to Pay and card reader transactions.

Currently, optional donor tips are unavailable in the mobile app, and transactions incur platform fees even when tips are enabled on the campaign.

Use case:

Organizations collecting in-person donations or selling tickets through the mobile app would like to offer supporters the same optional tipping experience available through Givebutter's online checkout.

This would provide a more consistent checkout experience across payment methods and give organizations an additional way to support Givebutter's optional-tip pricing model.