Baby play

Hi all – I'm just curious to know what you are all doing to play with your babies… My LO gets bored very quickly nowadays. He has a sit me up, a play mat, and a bunch of little handheld toys but he gets bored after each of them within 5 to 10 minutes. It's frustrating because I literally have to spend the whole day holding him and doing nothing else bc he doesn't like his play spaces. We sing a LOT, go for walks, I take him in front of a large mirror, and we read books. But that all only fills so much time. Any other ideas would be very helpful :-)