AlphaTots and TallyTots by Spinlight Studio are great apps to learn ABC's and 123's. My 4 and 6yr olds love these apps. They enjoy all the wonderful things to learn from them.
AlphaTots is all about learning your ABC's. There is 26 letters with all different kind of interactive activities to make this app enjoyable and hold your childs attention for a long time. There is a sing-a-long song for the alphabet and kid friendly navigation. This app is only available in english. This app promotes fine motor skills along with learning the alphabet as your child does each activity for each letter. I also liked that it sounded out each letter sound promoting early reading skills for your child :)
TallyTots is all about learning your 123's. Your child will learn their numbers from 1-20 with this app with a whole lot of interactive activities along the way. I love that they cheer your child on while working with this app as they finish an activity. The activities are fun and promote fine motor skills along the way for example the number 1 has you turn a lightbulb on by holding your finger down on it. There is a sing-a-long also included with this app all about numbers. This app is only available in English. :)
I highly recommend these apps and hop you will also check out the other apps offered from Spinlight Studio :)