From time to time you may see notifications about new features or product update. There isn't a way to prevent you from seeing them (although you can tap on the X to make it disappear) but I can forward specific complaints to our mobile team to make sure you're not getting these notifications in error.
You should not be seeing third party ads.
It would be helpful to be specific about the ads you saw, the frequency of ads, or if it's an ad for something you already bought, etc. The more information you provide, the better we can troubleshoot if it's an actual bug within the app as well. http://content.dictionary.com/about/contact