Although both the D3400 and the D3300 lack Wi-Fi compatibility, the big jump forward for the D3400 is the camera ' s compatibility with SnapBridge, the Bluetooth technology that Nikon now uses to connect the D3400 (and other Nikon DSLRs) with mobile devices.
Even though the D5600 is a svelte little camera, it's got a sizeable 3.2-inch touchscreen LCD. The touchscreen alone is a handy feature for beginners because it makes it much easier to navigate the camera's menu system (which you can bring up with a single touch) and for focusing when shooting in live view.
The Nikon D3300 is an entry-level DSLR with an impressive spec list, including a 24 megapixel sensor and 1080/60p HD video recording. It provides the right level of controls for a beginner, offers a number of in-camera retouch options, and boasts excellent battery life.