I must admit I’m guilty of letting our kids play with iPad and iPhone. I don’t see any problems about that. However, instead of touching just a plain screen here’s some other things to explore.
To obtain understanding about nature let your kids play with real nature. Caterpillars, regardless of their size, are great to start with. Here’s Sienna with an almost full-size caterpillar of the Death-Head Hawk moth (Acherontia atropos) and a young caterpillar of the Small Tortoiseshell (Aglais urticae). Learning nature is learning diversity, as well.