The new iPad’s Retina display is its flagship feature; by all accounts from reporters who attended the third-generation iPad’s unveiling this week, its 2048-by-1536 pixel display looks exquisite in person, with crisp text and vivid color saturation. But the much improved screen may severely limit how you use the tablet.

That’s because in order to take advantage of that display, apps need to generate new versions of their graphical assets. The new iPad sports four times as many pixels as its predecessors, so for Retina display support, apps need new images that are twice as wide and twice as tall as before. The physically larger images, of course, wind up as larger files in terms of megabytes, too. And that’s going to become a problem pretty quickly given that you can’t upgrade your iPad’s hard drive. It’s unfortunate that Apple didn’t double the new iPad’s storage space options to 32GB, 64GB, and 128GB to better accomodate the larger app sizes endemic to Retina-ready apps.

How big is big?

Let’s look at some of Apple’s own iPad apps to see whether fretting about how Retina iPad graphics affect file size is a waste of energy. It’s not a perfect comparison, since Apple also added some features to the apps it updated with Retina compatibility, but it’s still informative:

Keynote went from 115MB to 327MB; Numbers increased from 109MB to 283MB, and Pages went from 95MB to 269MB. With the exception of iMovie (which also added in new support for iMovie Trailers as it ballooned from 70MB to 404MB), these apps increased their file sizes by a factor between 2.5 and 3. (iMovie is nearly six times larger than before.)

Suppose a new 16GB iPad owner wants to load up the tablet with Apple’s Retina-display ready apps: the iWork suite, the iLife suite, iBooks, Find My Friends, Find my iPhone, iTunes U, and Remote. That’s 2.24GB of apps before you’ve downloaded a single third-party app, or synced a single song, photograph, or video. Remember too that a 16GB iPad really only offers the user around 14GB of storage space; the other two gigabytes go towards the operating system and stock apps. So now your 16GB iPad offers you fewer than 12GB of storage space.

My colleague Serenity Caldwell already wrote about the impact of Retina-ready apps on Apple’s freshly-raised limit (to 50MB) for downloading apps over 3G or LTE. In that story, she provides examples of other apps that swell in size with Retina-ready graphics. A smaller app like Tweetbot, for example, will reportedly grow from 8.8MB to 24.6MB. Larger, graphically intense games that weigh in between 300MB and 500MB today will likely require 750MB to 1.5GB once they update their art assets.

This doesn’t just affect new iPad owners

And perhaps the most worrying effect of the new iPad’s Retina display is its impact on older owners of both iPads and iPhones: Universal apps—that is, single apps that run on both devices—will become much larger even if you don’t own a Retina-display iPad. When Apple pushed out its Retina-ready upgrades earlier this week, I couldn’t successfully update my iPhone until I deleted my music and a few large apps. My iPhone can’t take advantage of the massive graphics that those apps need to embrace the iPad’s Retina display, but it gets no choice in the matter.

It’s a bit like Mac apps that could run on both Intel and PowerPC processors. If your Mac has tons of free storage space available, it doesn’t matter. But if your drive is close to full, you can use various third-party apps to remove any PowerPC-only code within your apps—since that code is useless on your Intel-based computer—to free up space.

Apple hasn’t coded a means by which your iPhone could ignore iPad-only assets when it installs universal apps. In fact, most developers also will choose to keep art assets specifically for the first two iPads, in addition to new art exclusively for the third-generation iPad; trying to force the older iPads to show downscaled versions of Retina iPad artwork would slow things down too much, developers tell me.

So we end up with a situation where iPhones contain iPad graphics they can’t use, iPads contain graphics for other iPads they don’t want, and iPads hold onto iPhone-specific graphics they don’t need.

Memory isn’t free

The problem is that flash storage isn’t free—hence the $100 difference in price between the current 16GB and 32GB iPad, and the 32GB and 64GB iPad. More storage costs Apple more money, and Apple surely doesn’t want to raise the iPad’s price tag.

At the same time, Apple is the only company around that could possibly drive down flash storage prices even further—by buying up millions of drives from suppliers to use in the new iPad. It seems, however, that Apple can’t yet find a way to keep the iPad’s current price point while increasing its storage, and considered the current state of affairs the best compromise.

If Apple’s right that it can’t yet drive down the price of flash storage further, that makes the software solution of letting iOS devices avoid storing in-app assets that they can't use even more imperative.

Two fixes

Really, then, I’m pushing for two separate but equally important fixes. Apple needs to bump the storage capacities on its iPads (and, frankly, iPhones). And it needs to devise a means by which in-app data that your iOS device can’t use won’t clog up your available storage space.

Coupling more storage with less per-app cruft will solve this storage crunch problem, and it’s one that I suspect more and more iPad buyers will encounter in the months ahead.

My advice to people asking me which iPad to get today is to focus in on the pricier 32GB model, because once developers update their apps for the new iPad’s Retina display, 16GB simply won’t be enough.

[Lex Friedman is a staff writer for Macworld.]