In the recent Phoenix Wright event, Phoenix Wright 123HD was announced for iOS devices. The game has been remastered to look sharper and includes all of the first 3 Phoenix Wright games.
The game is currently slated for release on iOS devices with iOS5. This means that the old first and second generation iPod Touch and iPhone are not included, but any device newer than that will run it fine. There are also plans for an Android version in the future.
Capcom will be using a pricing model to entice users to buy all three at once.
Phoenix Wright: Ace Attorney (Turnabout 1-2) - FREE
Phoenix Wright: Ace Attorney (Turnabout 3-5) - 600¥
Phoenix Wright: Ace Attorney: Justice for All (Turnabout 1-5) - 600¥
Phoenix Wright: Ace Attorney: Trials and Tribulations (Turnabout 1-5) - 600¥
Complete set (all turnabouts inclusive) - 1200¥
No confirmation of a localization yet, but I can't imagine why it wouldn't show up. Exchange rates put a 600¥ app at roughly $8, but given the general price of apps on iTunes in Japan, I'd say that it'd show up as $5 or $10 for the set.