In the middle of winter there can be few more spine-chilling thoughts than the idea of slipping into the ocean for a dip. But at least one group of people are attracted to the idea year-round: scuba divers.
While high technology and water don't mix well as a rule, the smartphone and tablet revolution has expanded to diving. Divers now have many apps to help them plan, execute and even train for their dives.
For beginners who need to pass certification tests before they can dive freely, the Scuba Exam app (a restricted-feature version is free on iOS and on Android) is an ideal helper. Novice divers will enjoy its short history of diving, back to early diving-bell experiments by Guglielmo de Lorena in 1531. It also has a dictionary of diving terms and expressions, and you'll get more terms with the app's full version on iOS and Android ($4 each). But the app's main feature is a practice quiz about best diving practices, with plenty of questions to prepare you for your diving qualification test. The app is not pretty to look at, nor is it very sophisticated. But the simplicity of its straightforward design will be useful to help you refresh your knowledge in your spare moments.
For seasoned divers, apps can help you log dives; you can enter data on your smartphone while every detail about the dive is fresh in your memory. The $12 iOS app Dive Log offers one of the most comprehensive diving logs. A quick tap on the "+" button takes users to a prompt to either enter a new dive in an empty template, or use the last dive's log as a template. The interface for entering dive data is intuitive -- twirling dials to set dive depth, for example, or choosing from a prepopulated list of dive types (like "fun" or "wreck"). It can even sync with dive logs on your computer, show you your overall diving statistics and keep track of your diving buddies' details. The one criticism is that the app is so complex that it's easy to get a little lost in its menus.
Diving Dude (free on iOS) offers a similar experience, and even has a few social networking features. You can, for example, see your buddies' recent dive experiences in detail. It's more cheerfully designed than Dive Log, relying more on icons to simplify logging dive details like water visibility or weather conditions. But the app feels slow to respond in some places, and you have to scroll down to the "save" button to save data, a step that is easy to forget.
The free Android app Dive Log offers a basic, text-based interface. But it doesn't skimp on functionality. Like the iOS app of the same name, it lets you log detailed dive data. Divers who like to keep precise track of their experiences may even prefer it to the iOS alternative.
To help with compressed air calculations, iDive Nitrox ($2 on iOS) is a simple no-frills app. On its single screen, you enter your planned depth and other details, by using sliders or typing in figures. The app immediately gives critical data like the best blend of nitrogen and oxygen to use. The free Nitrox Calculator app for Android is similar in function. These apps also caution you that they are not meant to replace your own calculations; they're best used to double-check yourself.
Knowledge of tides and currents is critical to divers, and many apps promise to help. For worldwide tides, Marine Tides Planner (free on iOS) has a long list of global ports, and delivers tide predictions with clear charts and numerical tables. Its map interface for selecting locations is a bit confusing, but you can mark locations as favorites. You'll probably tap most often on those favorites and rarely have to worry about the map. The app is free for basic tide predictions, but for more precise tidal calculations there's an in-app purchase option.
The free Android app Tides & Currents does an equally fine job of predicting tides in the near future. This app has a slightly confusing alphabetical list of locations, but you can configure it to report ports nearest to your location. It has a basic interface and the tidal data display is clear and uncluttered.
Whether you're an occasional diver planning a winter getaway or a regular, happy diving!
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This article originally appeared in The New York Times.