If hiking sounds suspiciously like exercise, don't forget that lazing around on a picnic blanket reading a book counts as being outside too. If you need something new to read, Goodreads can recommend new books and let you know what your friends are enjoying—just amble down to the library or bookstore and fire up Goodreads' free iOS or Android app.
A Marvel Unlimited subscription is only $10 a month if you want to spend the whole weekend discovering new comics or revisiting your favorites. For the price of a ticket to the latest superhero movie, you could read the same characters' entire stories. The app (free for iOS and Android) even have plenty of free issues to whet your whistle.
Still going strong? You could blow an afternoon geocaching—that's using your phone's GPS to search for hidden treasures left behind by other geocachers—and the free Geocaching app for Android and iOS makes it easy to get started even if you've never tried it before. Once it gets dark, Star Walk ($3 for iPhone and iPad) uses augmented reality to overlay stars, planets, and constellations over the night sky. It'll make the same old sky over your same old house look downright magical.
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