From TomatoCart Wiki

The upgrade guides here is provided by TomatoCart serving as an tutorial for users who want to update previous version to the latest one. Please find your current version below and do the upgrade step by step.

TomatoCart v1.1.1 to v1.1.2 Upgrade Guide!
TomatoCart v1.1.2 to v1.1.3 Upgrade Guide!
TomatoCart v1.1.3 to v1.1.4 Upgrade Guide!
TomatoCart v1.1.4 to v1.1.5 Upgrade Guide!
TomatoCart v1.1.5 to v1.1.6 Upgrade Guide!