The Basic Edition of DivisiBill is free and does not show ads. It can handle most bills, but it is possible to purchase a couple of additional features on the settings page. You can use this page to upgrade to the Professional Edition or buy packages of OCR scans (for more details on OCR, see below).
The Professional Edition subscription enables automated cloud storage and backup for bills, venue lists, people lists, and selected program properties. In the Basic Edition, you can use the archive and restore buttons on the settings page to back these things up. The settings page for the Professional Edition has some additional options in order to support automated cloud backup.
OCR stands for Optical Character Recognition. In DivisiBill it is used by a cloud-based service to scan a picture of a bill into item names, amounts, and a few other useful values (tax, for example). It cannot help you distribute the cost of items - only you know who the participants were and what each one had - but it can take a lot of the tedium out of the item data entry process and make it less error prone.
Each OCR scan costs a few cents. You can buy them in blocks in both Pro and Basic Edition. You will retain any OCR credits through an upgrade or if you uninstall and reinstall DivisiBill.
Modern mobile phones can take very high resolution pictures, which are unnecessarily large and detailed for OCR. DivisiBill reduces the resolution and converts the images to black and white to save storage space and analysis time. Despite this compression, bill images are relatively large and so are not saved in a cloud backup or in an archive.