Specifically, I'm referring to Craig 738 tablets. These have been sold for $100 and less (I paid $88) at a couple of chain drugstores in the USA (CVS and Rite Aid). Although I'm no expert, willing to risk posting misunderstandings, these tablets surely seem to have quite-decent hardware, and most of the firmware is probably excellent, as well. The display is just lovely, especially its resolution, even if a little particle is trapped (apparently) underneath the touch sensor, in mine.
Based on both personal experience (lots of grief, one exchange) and reading some threads, these tablets don't seem ready for market. I know that's a strong statement. It wouldn't surprise me if Craig 738 non-specialist dealers have a horrifying return rate (and probably too many unhappy customers).
I don't have a functioning cell phone, much less a smart one (which is really a diminutive handheld computer, after all), so it was new to me that many Craig tablet owners wanted access to the Android Market (a Web site). The Market offers lots of both free and paid (low cost!) applications ("apps") that Craig tablet owners would like to have.
Recent emphasis in some threads has been trying to get access to the Market (often just "market").
Craig 738s (suffixes A and b (not "B", yet, if ever) have significant problems establishing a wireless connection, perhaps in no small part because at least some fixed-location wireless-access devices are in a sense incompatible with Craigs. There seems to be some auto-configuring happening, but by no means enough for the average, non-technical owner.
I have FiOS (Verizon fiber to the living room, in my case, affordable 25 Mb/s symmetrical), and a Verizon-specific Actiontec router. It has its own not-surprising IP (almost as generic as 127.0.0.1), namely, 192.168.1.1. Going to that IP with a browser brings up an excellent Web-style site (from firmware in the router, more than likely), with what amount almost to embedded tutorials. (Without those, I would have been hopelessly stuck.)
After several (make that numerous) attempts to connect (it says "scanning" until the Universe ends) --- essentially by semi-informed experiment, I finally succeeded (after replacing my firmware, partially "rooting"). I posted details elsewhere.
At last, in the Grand Icon Collection was "Market". I had a look, found some free apps that looked interesting enough, and downloads were refused.
(Yes, I had to create a Google account to reach the catalog page of app icons.)
Slept on this failure, and it rather slowly and gently hit me.
___ No SIM card!
I pulled up Wikipedia (love to edit it), and had a look
[SIM card] article. Did some copy edits, and added the metric approx. dia. of a US dime to a caption. Oodles to study; not now.
Woweeee. Good grief. Small wonder that I couldn't download. Authentication, identity (unique and maybe otherwise), encryption (likely?), as well as cellular-tower handshakes seem all to be involved before a transaction (free or paid) succeeds. Hence the question in this topic's thread.
The way it looks to me, who hasn't learned much about all the inside[r] complexity, Android Market essentially requires all
the attributes of a cell phone to make a successful transaction.
Ever tried Ethernet on a Craig 738? The firmware is there, but not the hardware. (That's not the only such instance, either.) Similarly, there's no receptacle/connector to hold a SIM card. That's the easy part. As well, the firmware is required, and it just possibly might be there, but afaik the tablet would also have to be registered with a cell phone provider to permit authenticating your tablet.
When you place a cell phone call, there's a lot of "handshaking" going on, probably some of it being "challenge/response" "flavor". The process of originating (and, probably even answering) a call, in detail, is anything but simple, it seems. A lot, perhaps nearly all, of this is missing.
Lest you have doubts, I'd like to have an app. collection as much as anyone else, but simply seeing the Market catalog page* is probably only 5% of what's needed. *Web pages are more akin to scrolls than sheets of paper.
In some ways, I'd like to be proven wrong.
Nevertheless, I had remarkable success downloading from only the A, B, and C parts (selections, at that?) of Project Gutenberg via another Web site that was new to me. Good grief, all of Tom Sawyer while on the throne in just a few seconds?
Non-malicious midnight hacker in 1960
Totally away from computers '62 to '81