Even-Flo is a brand (US, I think) that makes baby stuff.
Exersaucer is a bit like a baby walker, but instead of wheels it has a base, and the seat is surrounded by a ring with different toys, so baby can swivel round and play with different things. Ours has some musical items to press, some rattles, a teether, a squeaky toy (which tends to be used as teether!), an unbreakable mirror, and so on. It also has springs, so when he gets excited, he can bounce up and down.
As I understand it, baby walkers and door jumpers are frowned on by the experts in US and Australia (I spent a trimester in each country), although I learned to walk in a walker; and even time in a saucer is supposed to be limited.
By the time we put our baby in the saucer (a hand-me-down, so we didn't have to fork out for it!) he was sitting up and able to support himself.
The key to a strong back is lots and lots of tummy time (but not right after a meal, as I found out)!
