As soon as I found my way around my new iPad 2, and discovered that the Clock app from my iPod Touch was missing, I went searching through the iTunes Store.
"Classic Clock free" (hereafter CCf) pretty faithfully replicates all the features of the Apple iOS-for-iPhone "Clock" app. The trade-off for the free app is discreet AdMob ads just below the title bar. They occupy a band across the screen about 1/2 inch tall. In the alarm clock mode they disappear after a bit, if Auto Hide Menu is turned on. In the world clock, timer, and stop watch modes they continuously cycle through. The screen shots in the iTunes Store description fail to show them.
Why I give it only 4 stars: Ian J., reviewing the paid version (Classic Clock 1.3.1), correctly complained that when the alarm goes off, and you touch to silence it, CCf swaps in, replacing whatever app you happen to be using. With fast app-switching available, this would usually be no big deal for most apps. After CCf has swapped in, you have to touch Stop again to lock it down, or it sounds again in about a minute. That is admittedly irritating.
And, if iPod is playing on your iPad when you launch CCf (or it swaps in while you are trying to silence it), your music or podcast is suspended. You have to complete your business with CCf, swap to iPod, and touch to resume the music or podcast.
Other features:
Weather: It shows a current conditions symbol + temperature, available only with the World Clock mode, contrary to the screen shots in the iTunes Store. The screen shots also show a verbal description of conditions, next to the temperature in World Clock mode. Again, that is missing in CCf. (The settings panel for the alarm clock has a “Show Weather” switch, but it has no effect.)
You add time zones to the World Clock by typing in the names of prominent cities. The available list is long but not exhaustive. Missing: Providence, RI; Tampa, FL; San Jose, CA; Pretoria, South Africa; Tel Aviv, Israel; Glasgow, Scotland… I assembled 22 cities on the display (4 3/4 visible at one time), while looking for missing ones. It is hard to see in the screen shots, but the time zone abbreviation is shown above and to the right of the time.
Custom color for LCD: When you select Alarm, you get an alarm clock with LCD display. You can select from 4 predefined colors, or define your own with red, green, and blue sliders.
iPod music alarms: You can choose a song from your iPod music library to sound at the alarm time. It will play the first minute of the song and then repeat for I-don’t-know-how-long, if you don’t silence it. You select songs from your library via an alphabetical list of song titles with no thumb index. It could be tedious to select, say, "Yellow Submarine", if your whole iTunes library is in your iPad.
Simple and easy to navigate UI: It actually took me quite a long time to figure out how to access all the listed features and decide that they are mostly all there and work.
Slide up and down to dim screen: There is no visible slider. The whole screen is the slider: touch anywhere and slide up for dimmer, down for brighter. The maximum brightness is limited by the brightness setting in the iPad’s Settings app.
“[E]xtra FUNCTIONS” in paid app: At least according to the features lists shown in the iTunes Store the only difference to the paid app is no ads. I.e., no extra features are listed for the paid app.
All in all this is not bad at all for a free app. When they fix the swap-out-the-active-app bug, I will buy the paid app. (They should also get their features and screen shots in alignment.)
Meanwhile, after you download CCf, if you have any interest in science, or especially astronomy, for a very different kind of clock, check out Emerald Observatory. It is beautiful and does not have that bug. (I have no connection whatever to the developer or seller.)