**You cannot do this.**

A [delete feature has been requested][1] and [requested again][2] (with [tag:status-planned] given about 3.5 years ago).

Register your desire for this by **immediately upvoting these posts**:

 1. [Deleting an application key?][3]
 2. [How to delete an OAuth (2.0) API key?][4]

(*Theoretically*, if those feature requests get enough upvotes, they might get some developer love.)


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For now, if you really want to delete your app (there's probably no real need to), you *might* try asking Stack Exchange directly via [the contact form][5].  Personally, I wouldn't bother for something this trivial.


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Meanwhile, you can pseudo-disable your app by doing the following:

 1. Reset your *Client Secret* [(Click for larger view):  
  ![client secret reset][6]][7]

 2. Edit your app's settings to the following "safe" values:
    1. **Application Name:**   `**Delete me!**`
    1. **Description:**      `No can haz!`
    1. **OAuth Domain:**     `bad.invalid`   (Which is "guaranteed" bad per RFC 2606)
    1. **Application Website:**   `bad.invalid`
    1. **Application Icon (optional):**   leave blank/empty
    1. **Stack Apps Post (optional):**   leave blank/empty
    1. **Enable Client Side OAuth Flow:**   leave unchecked
    1. **Disable Desktop Application OAuth Redirect Uri:**   checked

Once you set those values, it will be ever-so-much harder for bad guys to hijack your app and do unspeakable evil with it. ;)    


  [1]: https://stackapps.com/questions/212/deleting-an-application-key
  [2]: https://stackapps.com/questions/2910/how-to-delete-an-oauth-2-0-api-key
  [3]: https://stackapps.com/questions/212/deleting-an-application-key
  [4]: https://stackapps.com/questions/2910/how-to-delete-an-oauth-2-0-api-key
  [5]: https://stackapps.com/contact
  [6]: https://i.sstatic.net/DJ5GIt.png "Click for larger view."
  [7]: https://i.sstatic.net/DJ5GI.png "Click for larger view."