Since I have a mac, an iPhone and an iPad, it is a very nice thing to be able to add and subtract data on any of the three devices and have it update across all three.

So far I have used myNetDiary, which has an iPad and a website version that are very good at syncing with each other. I also use and like GroceryIQ, which has both iPhone and iPad versions, making it easy to do my changes on my bigger iPad, but carry my more portable phone to do my actual marketing.

So what other apps have multi-device versions that sync? I'm interested in anything.

Things I use that sync to all my devices, either with the same app or with apps compatible with the same cloud service. Apps asterisks work with Android devices too.

* Evernote
* Toodledo (to do manager) (web site for computer)
Things (to do manager) (Switched to Toodledo when I needed to add my Android device)
Bento (database)
* HanDBase (database) (Don't use this, but been thinking about it, because It will work on Android)
* Kindle (eBooks)
* Reeder (Google Reader RSS Feed) (Different app for Android) Mac OS X version is beta through Mac App Store
* DropBox (cloud file storage)
* 1Password (secure password, notes, and info) (syncs through DropBox)

Oh, and I have MyNetDiary too.