FORTUNE — Reading anything long on a cell phone has never been very appealing. There are options — Instapaper will save magazine articles for you to read offline, Kindle and iBooks have adequate mobile apps — but in general, none looks great. Whatever the exact reasons, trying to tackle a substantial work on a micro-screen is wearying. Reading a book on a Kindle, Nook, iPad, or any other tablet, meanwhile, affords a larger screen and often, well, more breathing room.
Oyster, backed by Peter Thiel of Founders Fund, Hunch co-founder Chris Dixon, and others, may be a temporary panacea: It offers the most aesthetically pleasing smartphone reading experience to date. The app provides a channel to more than 100,000 books on your phone. For $9.95, you get unlimited access to books and can add or drop any at any time (the app saves the last 10 you’ve opened for offline reading). In theory, the service could be a godsend to avid readers: a turbo-charged, 24-hour mobile library — personalized. Of course, Google (GOOG) and Amazon (AMZN) loom large as giants that could, it would seem, make Oyster obsolete with great ease (particularly Amazon with its formidable e-library). But ignoring the business implications for a moment, I wanted to evaluate Oyster simply on a user experience basis, as someone who reads a couple novels each week and usually prefers to do it on dead-tree material.
The only clunky trait of the app is in the setup: It is currently invite-only; you request an invite by mobile or online at its website, and once you’re in (my wait was two days), it’ll email you to download the app and set up an account. Only once you’ve paid your $10 — there is no free test-drive option, but you can cancel membership at any time — will it ask you to choose five books to start with.
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“Unlimited books” is Oyster’s motto, but for now, the library, as large as it is, feels limited. I first searched for This Bright River by Patrick Somerville, but Oyster didn’t have it. I searched for the novels Lolito by Ben Brooks, Duplex by Kathryn Davis, We Were the Mulvaneys by Joyce Carol Oates, A Thousand Acres by Jane Smiley, Leaving the Atocha Station by Ben Lerner, All That Is by James Salter, Watergate by Thomas Mallon, and The Box Man by Kobo Abe. Oyster had none, so I tried some nonfiction I’d been meaning to read: the crime mystery Lost Girls by Robert Kolker and the animal behavior book Wild Ones by Jon Mooalem; no luck. Oyster had none of the first 10 books I searched for. (It had only one John Irving novel, also a travesty.) Unsurprisingly, pop best sellers are better represented. A “popular on Oyster” menu suggests, for example, Water for Elephants by Sara Gruen, The Art of Racing in the Rain by Garth Stein, and Starbucks CEO Howard Schultz’s book Onward.
It may be unfair to knock the app for some missing titles at the outset; the company says it takes 90-120 days to get a new release. (Of those first 10 that I sought out, four were indeed new releases.) Selection is an issue for Hulu and Netflix, too. For those looking to discover a book spontaneously, Oyster will do just fine. On the mobile home screen, under your current books, the app offers a “spotlight” of curated, themed collections like, “the end of summer” and “around the world.” These encourage discovery. What Oyster cannot yet be, it is clear, is a total replacement for the library or bookstore for those who like to read new fiction.
There is, inevitably, a social element too, Oyster’s attempt to double as a recommendation engine: Your profile shows which books you’re reading and have read, and your ratings if you choose to rate books. (You can, however, choose to “read privately.”) Friends that have Oyster can follow you and recommend titles to you, and the app will also recommend based on what you’ve read in the past.
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What really matters: The reading experience is clean and visually unobtrusive. Print size and font are easily, instantly adjustable. In contrast to the horizontal leanings of the functions on a tablet, the Oyster design is suited to the tall, thin iPhone: you turn the page not by swiping left, but by moving your thumb up, and the progress meter is vertical, on the right side, not horizontal along the bottom. Another smart, subtle design detail: At the bottom right, where you can see how many pages are left in the chapter, it also gives an estimate of how long it’ll take (“23 minutes, 37 pages left”), just as Longreads and other sites post articles with the average reading time attached. (Some Kindle models also show remaining time.)
What you cannot do is highlight a passage you like or take a note. In that regard Oyster doesn’t stack up to iBooks or Kindle, both of which allow you to highlight a line and write a note for export later. (Then again, you could always screenshot.)
I’m not sure that I — or, likely, many other readers — will ever read a great number of books on a phone. I’d plunge into a novel that way only if it’s one I’m dying to devour, and because of my affinity for brand new books, Oyster won’t usually have the ones I want to read. But in a pinch, it’s a lovely-looking option. For now, it exists only for iPhone, but an iPad version is coming in the fall and will boast, “even more personalized features,” an Oyster spokesperson says.
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Oyster is easily worth the reasonable $10 per month even if just for the ability to have books to read when you’ve got nothing on hand but your phone. But it still handles just one reading-related need: book supply on mobile. There are other needs that other apps and sites have attempted to handle, but remain unfulfilled. One: a review site or app that collects not just subjective, often-amateurish user reviews (the way Goodreads, a sort of Yelp for books, does, giving them an aggregate out of five stars) and not just high-level reviews from the Times and other critical outlets, but all reviews in a more binary, Rotten Tomatoes-style system (i.e. plain and simple, 78% of people liked this book). Another need: a reading app that makes it easier to jot a note or underline a passage and instantly save it somewhere other than inside that app. Another: a reading app that isn’t just for books, or magazines, or one-off articles saved from the web, but all of the above.
What tech-savvy literary folks need, still — and Oyster may or may not fill this gap eventually — is an all-in-one app, available across all phones and tablets, that allows for reading of any materials — books, poetry, comic books, magazines, articles you’ve flagged from the web — with easy, seamless exporting of passages or notes, social sharing, and quick, do-you-recommend-it-or-not rating ability that would translate to a more useful database for anyone seeking their next free-reading choice. Think of it like a Facebook or Google focused squarely and solely on reading. All of it is doable already — let’s see how long it takes someone.
