These are all independent projects created by individuals that offer you other ways to check for breached accounts on Have I been pwned? If you've created something that's missing from this list, please get in touch.
Created by Matt Smithies and does just what it sounds like it does — a rich client app for your Android device.
This one by Björn Lundén and also does just what it sounds like it does — a rich client app for your Android device including details of the breach the account appeared in.
One for the Windows Phone users, this one is by Kamran Ayub and allows you to check any email address against the API and get back a complete list of pwned websites.
Recon-ng is a Python based reconnaissance framework for penetration testers built by Tim Tomes. A module designed to look for compromised accounts via the "Have I been pwned?" API has been contributed by Tyler Halfpop.
A little Gem by Carl Sampson that can enumerate through a collection of addresses and report on their pwned status.
Another Gem, this time by Michael Henriksen that can extract email addresses from a file then run them through Have I been pwned?
A Python implementation by Casey Dunham to quickly check a single email against the Have I been API.
Another Python implementation by Alexan Mardigian to enumerate through a list of email addresses.
More Python, this one by Eric Fay and with easy access to the main services provided by Have I been pwned? including breaches and pastes, but also including the ability to retrieve additional data such as all breaches and compromised data classes.
PwnedConsole is a Python script by Kory Findley designed to act as an interactive tool for querying Have I been pwned? for breach data. This script makes use of the PyPwned Python module.
A Maltego Transform by Sudhanshu Chauhan to to return all breached sites for a given account.
Searching for breached accounts has been added by Dashtag as an additional feature on this @SEKIMIAtweets existing app for webmasters and website owners that want to be alerted when their site goes down.
Another app by Carl Sampson, this time for iOS. iPC allows you to maintain a list of accounts to be monitored which you can then go back to and check regularly for more pwnage.
An Angular JS module by Brad Cavanagh that checks an email address for previous pwning during the signup process on a web form.
A Firefox OS app by Zshawn Syed that takes an address and and runs it against the API to check for previous pwnage.
An "If This Then That" recipe by Nick Scoman that use the RSS feed rather than the API to automatically send an Android notification when a new breach is added to the system.
Created by Gerald Versluis, these Xamarin based apps report on the top 10 breaches in the system plus allow for searching either via iOS or Android clients.
A plugin created by Evan Herman that allows a WordPress site owner to cross-check their registration database for breached accounts.
A couple of Node.js projects created by Justin Hall, both freely avialable via GitHub.
A browser extension by Antreas Pogiatzis which integrates directly with Chrome.
A universal Windows app built by Lance McCarthy and available for free in the Windows store.
An iOS app built by Vince Chan and available for free in the Apple app store.
A Telegram project built by Luke Anderson providing a quick and sleek way to find out if your data has been hacked.
A Microsoft Flow built by Jon Gallant that sends a push notification every time there is a new breach loaded into the system.
This one by Marc Doerflinger, "Hacked?" searches for data breaches an email address appears in and details the classes of information that have been exposed in the incident.
A Java client built by Dario Oreščanin that will check the API for breaches based on the provided email address.