TeuxDeux, my favorite simple to use and difficult to spell todo list application, has quietly launched an iPhone app. They’re apparently waiting to announce it later this week, but Tina Roth Eisenberg (the designer behind TeuxDeux) recently talked about it on The Pipeline with Dan Benjamin. The app costs $2.99 and supports all of the features of the free browser-based version plus support for multiple accounts, and it’s always in sync with your accounts on the website. You can buy the TeuxDeux app here (iTunes link.)

Facebook Places adds geolocation to Facebook, allowing you to share where you are, what you’re doing, and who you’re with. It differentiates itself from Foursquare or Gowalla, with an interesting additional feature: it allows you to check your friends in with you. This is a cool feature but it is certainly open to abuse; your friends could check you in somewhere embarrassing as a practical joke. Depending on who’s watching, you may find it causing problems for you.

Here’s how to prevent other people from checking you in on Facebook Places:

1. Click on Privacy Settings
   
2. Click Customize Settings
   
3. Under Things Others Share, disable Friends can check me in to Places
   

That’s it. I’d like to see the ability to select certain people or friend lists which are allowed to check you in (or filter out people and lists which are not) but for now it’s an all-or-nothing setting. I’ll update this post if the options around this feature become more robust in the future.