I have a flight from US that will leave me with a 3+hour layover at LHR. Need recommendations on places to eat, shop, etc.

I think it unlikely that you will be able to leave the airport with only a three hour layover. But, if you provide us with arrival airline and terminal, and departure airline and terminal, you might be able to get some good suggestions on this forum.

Every terminal is essentially a shopping mall and has several places to eat.

Which terminal(s) are you flying in/out of?

Was posting the same time as Jeff801. In case that is what you meant - you definitely won't be able to leave the airport.

I had not planed on leaving the airport. I arrive T3 and depart from T5 to NBO.

Then you'll probably have about an hour free (assuming you land on time) before they call you to your departure gate. Spend that hour at T-5 . . . .

here is the transfer process:

http://tinyurl.com/3wp8yk

Great link, thank you.

LHR has very few eating or shopping facilities outside the secure area (in English called "after passport control") in each terminal. After passport control, though, LHR terminals are really shopping malls with a few departure gates attached

Access to the post-passport control mall (including most airlines' CIP lounges) is generally limited to passengers departing from the terminal concerned, though there's restricted access to some airlines' Arrivals lounges for passengers arriving at a terminal

So in practice you can really only access shopping and eating at T5. A full list of what's on offer there is at the airport website.