Read-it-later apps like Instapaper and Pocket are handy for digesting large articles, but they're really just pulling up optimizing internet links. What if your favorite story disappears a few years from now? Pocket now has a solution to that long-term problem. Its new Pocket Premium service saves a permanent copy of any article you flag, giving you access even if the host site goes down or changes the content.The upgrade also brings in a deep search option that scours entire texts, and it suggests tags to help you find what you're looking for in the future. If archiving is your thing, you can sign up for Premium at either $45 per year or $5 per month. That's a lot if you rarely look at something more than once, but it could be a bargain if you can't bear to be without memorable reading material.