I tend to invest in companies that are riding some technology wave for growth, and who have network effects for defensibility.
The obvious wave Loop is riding is the trend towards privacy. The whole social market is getting disrupted and moving towards a privacy centric vision, creating a massive opportunity.
I also like their focus. They are laser focused on family. But everyone has family! So the market is both narrow and huge.
Lastly, this is photo sharing which has natural network effects. The team has proven they can execute, bringing a complex product to market and generating multi-million in revenue already.