Reading to her, and making books 'fun' and a normal part of life is the best thing you can do. 'Counting' matching one-to-one correspondence is all that is needed in number work. So count dolls, teddies, have 'tea parties', how many plates, cups, biscuits, cakes etc are needed for dolls.
If you can, involve her in shopping lists, quantities in the supermarket; recipes and cookery (if you can bear it).
REAL things are much better than any 'app'!
Cbeebies does plenty of early education things:
www.bbc.co.uk/cbeebies/shows/alphablocks
You obviously DO want to 'push' her, otherwise you wouldn't be asking. And the year won't be a WASTE if she is happy, playing in the garden, going to the park and doing the million things 4yr olds enjoy doing.
Jigsaw puzzles; safe scissors to cut up junk mail and Pritt stick to stick things in a scrap book; Lego and other construction toys. Try to let her CHOOSE what activities she wants to do, where she wants to go. So teach her to make decisions, and learn from any mistakes.
Learning to play an instrument, so a Keyboard is brilliant, if you can afford one (61 full size keys, not a toy one) or little xylophone, or 'kitchen' percussion' (safe pans and wooden spoon) to accompany music on radio or TV.
If you STILL want something more academic, I'll look back sometime with suitable web sites.