You can create as many of these are you require, allowing you to limit access as need be in the future.
To create a new key, log in to Endropper, then click the drop down in the top right to select the "Settings" screen.
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Select the "API Keys" tab to then load up the API Key listing page.
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Then click the green "Create New API Key" button.
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Give your new key a name (Note) and if you want to lock the key to a specific IP address, input this into the "Bound Ip Address" field (this is optional).
Hit "Create New API Key" and you're done :)