I recommend wooden breakfast trays with a pillow underneath, looks like this. It's comfortable and practical, don't have to deal with setting them up, just put it on your lap.
It also serves multiple purposes; you can eat food on it because it acts as a table, you can use it as a hand rest when reading/cellphone/playing portable games, of course it can be used as a laptop. I bought a set of matching ones for 45$, very useful.
Get a wooden one with a pillow underneath, it's comfy, allows the laptop to ventilate normally, can use it almost anywhere. Something like this