The issue of what iPad to buy is on my mind, as my in-law's iPad 2 is in need of replacement. This iPad was a Mother's Day gift in 2012, and suffered a drop that broke the screen shortly thereafter. Last August through November, the iPad was sent away for repairs with a company that I used to recommend (and recommend no longer), and the iPad arrived back in my hands–not completely fixed but working after I called the police in the repair company's hometown.
The iPad 2 returned with a new screen, hastily installed (scratches all over the frame) and not secure (only one side of the screen's adhesive was sticking). But it worked, and we had it back after a bad experience with the company–so we put it in a case that holds the screen tightly, and went forward.
Well, that iPad is acting up. Perhaps it is the replacement screen (now completely loose on one side) or the screen's internal connector–but a replacement screen repair (for an already replaced screen) will be $150-$200, and that just isn't worth it when you can buy a refurbished iPad 2 from Apple for $319, and even less on occasion (Woot sales, and so on).
So, it's time to sell that iPad (it's worth $75 from NextWorth in its current condition, and Best Buy is offering a $200 trade-in on working iPads over the next days) and to move to another iPad.
But what iPad should my in-laws buy, and what iPad should you buy?
Conclusion #1) An iPad with at least 32GB of RAM. With apps such as Notion taking up 1.7 GB of space, and academic iBooks weighing in at 2GB, it doesn't take long to fill a 16GB iPad. If you can afford the extra $100, a 64GB iPad isn't a bad idea, either.
Conclusion #2) Not an iPad 2. The iPad 2 is a wonderful device, and it changed how iPads could be used almost as much as the first iPad changed computing. The iPad 2 added a rear camera, but the 3rd Generation iPad added the Retina screen, and the 4th Generation iPad added nearly double the speed and the lightning adapter. We expect the next iPad this fall (perhaps October), and it isn't worth spending your money on a device that will be obsolete so quickly. Now, if someone gives you an iPad 2, run with it. But don't buy a new one right now.
Conclusion #3) Not an iPad Mini. The iPad Mini is a game changer because of its lightness and portability. All signs seem to indicate that the design of the iPad Mini is going to impact the overall design of the 5th Generation iPad this fall. However, the iPad Mini is not a retina iPad (i.e. stunning display), and it has the basic processor of the iPad 2 (although in tests, it runs faster than an iPad 2). Expect a new iPad Mini to (at the least) be significantly faster than the current iPad Mini, as well as thinner and lighter (there are mixed reports on a retina screen, so don't count on that for the fall). If you're going to buy an iPad now, and you won't buy the iPad 2–you shouldn't buy the iPad Mini. If you really want an iPad Mini, put your money in the bank and wait until the fall.
Summary: This leaves the 4th Generation iPad as the device to purchase. The 4th Generation iPad had a huge jump in performance over the 3rd Generation iPad, which in some cases ran slower than an iPad 2. This, by the way, is probably why Apple chose to break their yearly release cycle (right now, Apple is out of the cycle they established–no new iPhone in the summer, no new iPad in March)–they weren't happy with the performance of the 3rd Generation Device for the long-term. The 4th Generation iPad will be functional long enough to run iOS 7, iOS 8, and likely even iOS 9. If you are looking for a return-on-investment in terms of upgradability alone, the 4th Generation iPad is the way to go. Apple is selling refurbished models at the lowest prices I've seen, not counting Best Buy's current trade-in offer.
If you buy a 4th Generation iPad, you can be assured that the lightning adapter will not change, but many accessories will change for the new form factor of the 5th generation iPad, including cases. This means that you maybe able to take advantage of clearance sales in just a few months as retailers get rid of “old” stock to make room for 5th Generation iPad accessories. So–you can have an iPad that won't be obsolete for some time right now, and potentially save money on iPad accessories in just a couple of months.
As a side note, Apple's decision to release a new iPad in the fall, after the start of school, is a thorn in the side of many schools who purchase capital items over the summer. You usually want to start the year with an educational initiative instead of trying to do so mid-year. This means that schools will have to make the choice of the iPad 2 (which will be outdated much faster) or to spend more on the 4th Generation iPad, fully knowing the 5th Generation iPad is a few short months away. My school, which is moving to 1:1 iPads, is purchasing 32GB 4th Generation iPads–which is the best choice at the moment. And for the record, I did nothing to influence that decision nor did I have any say in the matter.