Recently Timehop got hacked and some data was retrieved from their servers. Now you might want to delete this app, because you feel exposed. Deleting the app isn’t everything. There are a couple of things you’ll have to do in order to make it effective.
An app linked to your social accounts gathers access tokens in order to get data from those accounts. You, the user, give the app permission to do so and can often select what the company may gather (like your e-mail address, photos or posts). An app like Timehop is fun, but requires a lot of data in order to function properly, so it’s an understandable target for hackers.
If you get tired of using an app, you can delete it, but that’s only half the work. They may still hold some data (and actually are required to keep some for a while in some countries) and even active access tokens. If a company gets hacked and the hackers get these tokens, they will have access to the same data the app had until the token is invalidated. Depending on the technique used, this token might be active for a while, meaning all new content (tweets, photos, etc) will be available as well.
To be safe, check your social media accounts for security settings and remove all apps and services you don’t need.
Some to start with: