Sago Mini is a good bet for preschoolers in general (disclaimer - I was part of starting Sago Mini, but have no connection to them now). You can buy them indivi

Sago Mini is a good bet for preschoolers in general (disclaimer - I was part of starting Sago Mini, but have no connection to them now). You can buy them individually and then I'd probably start with Sago Mini Pet Cafe or Sound Box. There's also Sago Mini World, which is a subscription that has loads and loads of things in one place. Other good options for this age group is the Peekaboo-series from Night & Day Studios and Petting Zoo from Fox & Sheep. If you're looking for something more educational, take a look at Khan Academy Kids which starts at around age 2. Fantastic and completely free.