One Up is a simple counter that you can increment or decrement manually or setup to connect to RetroAchievements.org to display information about your account and your progress. One Up is highly customizable and can update its display with your latest information with a simple key press of your choice, making it the perfect companion when hunting achievements, especially if you are streaming.
This application is open source and distributed under the Creative Commons NC-BY-SA license (no commercial use, credit the author and redestribute under the same conditions). Sources are available through a GitHub repository and you can also find the latest releases there.
When you start One Up for the first time, it behaves as a regular manual counter. By default you can use the + and - keys of the numpad to increment and decrement the counter. Thanks to the JNativeHook library, you can do so even out of focus, when another application is being used.
By clicking on “Application > Settings” you can customize the display by selecting fonts and colors and you can input your Retro Achievements username and API Key. This key can be found on Retro Achievements under “Settings > My Settings” or by clicking here. It's the string found in the "API Key" textbox.
After clicking on “RetroAchievements > Connect”, One Up displays in order: the game you are currently playing along with its console, the number of achievements unlocked for this game and the completion percent (Hardcore mode is factored in this percent), your score and true score (score multiplied by achievement rarity), your current rank on Retro Achievements and the latest achievement you unlocked for the current game.
Once connected, it retains all the functionality of the manual mode, allowing you to keep tracking achievement count manually if the server fails to respond. If an achievement fails to be awarded because of a bug, you can also count it manually that way.
One Up requires a Java 8 Virtual Machine. Check Java.com to update your installation if the application is not working. For Mac users, it is currently necessary to enable assistive devices for One Up to work, thus allowing it to capture your input even when out-of-focus.
To enable accessibility in OS X 10.9, open the System Preferences and click on “Security & Privacy”. In the “Privacy” tab, click on “Accessibility” and the lock icon at the bottom of the window. Once you have entered your password, tick the checkbox next to “Java JRE”. If Java does not appear in the list, start One Up once (it will crash) to make it appear.
To enable accessibility in OS X 10.8 or lower, open the System Preferences and click on “Accessibility” (“Universal Access” in older versions). Tick the checkbox that reads “Enable access for assistive devices” and enter your password.