The site describe the app this way:
Geofeedia delivers a one-of-a-kind, aggregated search experience for user-generated content by using the powerful API’s of Twitter, Instagram, YouTube, Flickr, and Picasa.
The verdict on “usefulness” from several new users is mixed. Some have found it invaluable, while others suggest it’s just one more tool in the toolbox, one that might be overshadowed by other journalists wielding hashtags on their findings.
Price is also worth considering. The preliminary subscription fee is $1,450 per month for up to five users. While pulling together all of the five services into a single app might save time, there are tools to spatially search these, many of which are free.
Data quality must be examined, too. Not everyone geotags posts and it’s common on Twitter for the location of an account to always be the owner’s home city or neighborhood. In short, the search tool can be no better than the raw data, which is itself, of highly variable accuracy.
That said, interest in a free trial is so high that new accounts are taking several weeks to process.