We got a small portable Bluetooth keyboard which can be used for lots of purposes, since it can connect to any compatible device; you can get the most out of it w.r.t devices without a physical keyboard like smartphones or tablets. The only issue is that the phone needs to be held in a position to see the (usually reflective) screen, which is quite hard if you want to type with ten fingers. This simple holder solves it in a cheap and useful way, capable of accommodating various devices, without modifying the keyboard or the device itself.
Step 1: You'll need a peg or two, aluminum foil, hot glue and/or Sugru
The base of the holder is a peg used for hanging clothes to dry, which are cheap and can be find anywhere in the world. You'll also need a small amount of aluminum foil (10 cm or 3" square is enough), and hot glue and/or Sugru. We used both, they solve a similar problem with different pros (Sugru can be formed with your hand at room temperature) and cons (Sugru hardens much slower), but if you have only one of them, that's fine. If you decide to use Sugru, you'll need a pack or two for each peg, we built two pegs which should be enough for most needs.
Step 2: Build a bottom pad for better stability
As you can see from the photos, the peg doesn't reach the bottom of the keyboard, so a pad is needed for better stability. We used hot glue for this, but Sugru is great too; the surface needs to be covered in both cases with aluminum foil to that the glue/Sugru doesn't stick to the keyboard itself. Build the pads in a way that it can support the peg but the peg can still be removed. After the glue/Sugru is ready, you can remove the aluminum foil around them, the second photo shows how it should look; the resulting shape matches that of the keyboard edge.
Step 3: Build the top pads to hold the device
We used Sugru for this, and is highly recommended as hot glue lives up to its name and can only be formed while it's hot. Build two small "hills" on the top of the peg in a way that a bigger can hold the back of the device, while a smaller prevents it from moving toward the keyboard, while not covering the display. With Sugru, you can use an actual device to make it perfect, but don't forget that it needs 24 hours to harden, and before that, it's more sticky, so make sure that your gadget would be held in place even after the stickiness goes away.