Nikon offers software development kits (SDKs) free of charge to those developing products and services that incorporate Nikon digital imaging products. Please go to https://sdk.nikonimaging.com/apply/
and fill out the SDK application. Since there is no listing for the WU-1a or D3200 on the form, choose any DSLR from the SDK list. When you get to the page of the form where you enter your contact information please describe your requirements in detail. If an SDK is available that fits your needs you will be sent downloading instructions.