I use Logitech harmony remotes for that. I currently have this model (though it is an older one and has been replaced with a newer one with home automation buttons:
http://www.amazon.com/Logitech-996-000118-Harmony-Smartphone-Refurbished/dp/B00L5H1IQM/ref=sr_1_10?s=electronics&ie=UTF8&qid=1463003047&sr=1-10&keywords=harmony
I also have the smart keyboard that joins with it so you can enter text easier and control my HTPC as well but you may not need that.
This system you need a iOS or android phone to do the setup which is not too hard. This system works by placing this hub device next to your equipment and you also get an external blaster to connect to the hub if your have equipment hidden or spread out a bit. The hub does all the sending of IR signals to the devices as well as bluetooth to some game consoles if required. It's great if your equipment is stored in a cabinet.
You can talk to the hub with any number of iOS/Android phone/tablets so they can become remote controls if you need them to and they talk over WIFI to the hub so anywhere in your house you have wifi signal they will work. The really small basic remote it comes with talks over RF and i've found it works for me fine about 30'/10m away through a couple of walls but don't bank on it working on the other side of the house.
It could be setup to control just one device but it is not ideal for this use case because it is an activity based control system. You load in your TV, AVR, bluray, xbox, cable box etc into its setup and then create activities like 'Watch TV', 'Play xbox'. 'Watch Movie' etc and when you push the watch movie activity button it turns on the TV, AVR and bluray player and sets the AVR and TV inputs for you. Choose another activity and it turns off what is not now needed and turns on the new source device and switches the input.
The other thing with this system is it doesn't work well for everyone if you keep your rack of 6 remotes on your coffee table. Every time someone uses the standard remotes the Harmony does not know about them so sometimes it won't switch properly. Most of the time just pushing the 'watch movie' activity button a second time fixes all these issues though as it re-sends the switch input commands to fix any problems. for most modern devices it works really well as long as there are good input selection remote buttons on your important devices. My only issue i have is that my TV IR sensor is not ideally placed as it is on an articulated wall mount and 1/3rd of the time it misses the signal and I have to push the activity button a second time.
You can also get much more expensive versions with touch screen remotes that make it easier to know what the current state is than the simple mini remote my one has. You are limited to having just one simple remote and one touch screen remote linked to the hub (and one smart keyboard) but you can have many mobile/tablets linked.
And one final thing I like about this system is the remote being rf does not need to be pointed at anything. normally with a remote we are so used to picking it up and bringing it to our face to find that fiddly rewind button and then extending our arm to point the remote at the equipment rack and jamming the button down until it picks up the signal. because the ir blaster in the hub is so close to the device you don't get missed signals for most devices (unless they are placed poorly like my TV!) so you just pick up the remote find the button and push it and it works.
Pictures of my harmony hub on my tv cabinet.
