I really appreciate your help. There are multiple ways to contribute to this project and make it even better.
Even though CardDAV-Sync works quite well on many devices and with many servers, there may be some bugs in it.
If something doesn't work as expected, please don't hesitate to send me an email with a brief description what you did and what doesn't work. To send me a log you can use CatLog or any similar app from the market.
rate the apps
I don't want you to write anything that is not true about CardDAV-Sync. Just give me five stars and write that it is the best app you've ever seen ;-).
provide a test account
CardDAV-Sync works well with the major open source servers. But some servers may still not work. Especially for commercial products by far the best way to get it working is if you can provide me a test account on your server. This way I can figure out what doesn't work and fix it quickly.
spread the word
Tell everyone about CardDAV-Sync and link to this site (http://dmfs.org/carddav/)
purchase the paid version
By purchasing the paid version, you allow me to spend more time working on CardDAV-Sync.