Open Source PHP Invoice Software for Linux

Kimai is an open-source time-tracking solution. It tracks work time and prints out a summary of your activities on demand. Yearly, monthly, daily, by the customer, by the project. Its simplicity is its strength. Due to Kimai’s browser-based interface, it runs cross-platform, even on your mobile device. With Kimai, the boring process of feeding Excel spreadsheets with your working hours is not only simplified, it also offers dozens of other exciting features that you don't even know you're missing so far! The layout is fully responsive, made for desktop and mobile usage. Every user can configure the data columns that should be shown, e.g. to prevent horizontal scrolling on small devices. Kimai was built to be extendable, and features can be added with plugins. Developers wanting to create them can use many extension points.