Hope this helps - from the website
Our next release of the Weight Watchers Mobile app for iPhone, iPad and iPod touch (version 1.7), has been delivered to the Apple app store for approval. Once Apple has finished their own testing of the app, which takes 2-3 weeks, it will be available for download.
This new version will include full compatibility with the ProPoints plan updates so when you've downloaded the new version you'll be able switch between a counting and Filling & Healthy day approach directly on the app on a daily basis and customise your settings.
Until Apple testing is completed and the new version of the app is released, you will not be able to switch between Counting and Filling & Healthy day or customise settings on the app. However, if you make these changes on the website they will be reflected on the current version of the app