by: Logan Chamberlain
"Appy" Friday! This week, we feature Poptropica Worlds, NASA and how to be a citizen naturalist, as well as another favorite from Duck Duck Moose. And don't forget to check out our video to see our top pick of the week!

Poptropica Worlds
Poptropica Worlds is a unique, COPPA-compliant virtual world filled made just for kids. Every island is a new adventure with puzzles, games and tasks that earn kids points they can then use to customize their avatar and their home island.
Cost: Free
Age: 7+
Platform: iOS and Android

NASA Visualization Explorer
NASA Visualization Explorer is a handy news source for kids to learn about the reaches of outer space. This app provides a curated collection of articles and features for early readers pertaining to NASA projects and to astronomy in general. And, the hefty backlog of content means your kids won’t run out anytime soon.
Cost: Free
Age: Rated 4+, Recommended 8+
Platform: iPhone, iPad, and Android Devices

Pet Bingo by Duck Duck Moose
Back again with another math game app from Duck Duck Moose. Pet Bingo, much like the other Duck Duck Moose apps, is a fun and cute way for your kids to develop math skills through play. This time around, the problems slant toward an older audience, with bingo games designed to test math skills through primary school (e.g. 4-digit addition and subtraction).
Cost: Free
Age: 4+
Platform: iPhone and iPad

Lumio Farm Factor
This farm-themed app doesn’t just reinforce math skills, but rather it uses games and visuals to teach young learners about multiplication and division. The levels progress and introduce important concepts like repeated addition, that are essential for young mathematicians. And (bonus!) it’s a good deal of fun.
Cost: Free for Lite, $2.99 for Full Version
Age: 6+
Platform: iOS

There are a lot of good science apps out there, but not a lot for a scientific community. iNaturalist changes that by introducing some fun social features to a reference-based foundation. Users can take pictures of specimens they see in nature (animals, for example), identify the species for reference, then upload the photo and geographic data. Community members can then access these posts on their maps, offering a fun tool for planning out nature walks and observations!
Cost: Free
Age: Recommended for older kids due to social features (at parental discretion).
Platform: iPhone