Don't use this app with network enabled or at all if you value your privacy. To me, this really sounds like they are pretty much mirroring the contents of your gallery to their servers. Disable network and use storage scopes if you wanna use it still.
User Content: We collect your personal information contained in any User Content you create, share, store or submit to the App, which may include photo, video or other image files, music works, sound recording, narration, written forum comments, information, data, text, scripts, graphics and interactive features generated, provided or otherwise made accessible by Zoomerang App.
Information about others: With your permission, Zoomerang may access your contact list available on your mobile device or in other social networks in order to share your User Content, or to invite your friends and contacts to connect with our Service. We may also collect information about others if you use our Service to upload, share and/or distribute User Content that contains information about others, including their name, image and online contact information.
Content and Metadata – User Content may be accompanied by additional Content such as a hashtag (e.g., to mark keywords), comments, or may include metadata like a geotag. This makes your User Content more searchable by others and more interactive. If you geotag your photo or tag your photo using others’ APIs then your latitude and longitude will be stored with the photo and may be searchable (e.g., through a location or map feature) if your photo is made public by you in accordance with your privacy settings.