According to TechCrunch, some of the Android devices out there, which presumably covers tablets as well as phones, experience rates in the 30% to 40% range. That compares to a 1.7% return rate for iPhones, which I think seems a bit low for a tech device. That speaks to the simplicity, design, build, and power of Apple's device.
Now, you should temper this report with a bit of skepticism. The source isn't named and is listed only as "a person familiar with handset sales for multiple manufacturers." That is likely an analyst with information gathered from various sources, but that is only an educated guess.
Even if the numbers are double the true return rates, 15% to 20% is still high. It casts a cloud on the 500,000 daily activation numbers that Google tosses about. Cut that by 20% and the number drops to 400,000, which is still a lot of devices. Some of the returns are no doubt for hardware issues. All devices experience a certain failure rate, so someone returns a phone and swaps it out for a new one. This, too, impacts the activation rate as one person has activated two devices just to get one that works.
Part of the problem is expectations. Most people shopping for a smartphone know what an iPhone is, which is the standard by which all other smartphones are measured. They are either talked into an Android device or talk themselves into one under the premise that the phones are usually less expensive than an iPhone and they are as easy to navigate and use.
What happens is they find it isn't as simple, and it isn't even the same user interface as you move across different brands. HTC puts Sense on their Android phones, Motorola uses Blur or Droid on some of their phones, and Samsung has TouchWiz. Manufactures love to put their own custom user interface on a phone, thinking it improves it and makes it desirable. It often causes performance issues though, as is the case with the Droid 3. Even when the UI performs well, it may not be as well designed. No one would argue that these manufacturers have as much experience designing user interfaces as Apple has.
This means if someone looks at a friend's Android phone and likes what they see, there is no guarantee they will get the same thing if they go out and buy one, unless they get the exact same model. This no doubt contributes to a higher return rate.
I'll be curious to see if Google or its OEM partners refute this data with real return rates, or if they just give a collective "nuh-uh."