Another vote for Hubsan! I love my Hubsan X4 for indoor use (and outdoors if it's calm). I bought 8 of them for Xmas and gave them to my relatives. It was absolutely a crazy scene with half a dozen flying around at once (no apparent radio cross talk either which I was surprised about).
For my own indoor enjoyment, I have the smallest X4 H107L, the H107C (has on-board camera recording to micro flash just for fun), the H107D FPV (currently broken awaiting to hear back from Hubsan) and a Blade Nano QX.
All of them are fun and can help you learn to fly the Phantom better. I am less keen on the Blade though for two reasons- 1) price point is quite a bit more expensive than the base model Hubsan (even after adding a prop guard) and 2) there is very little warning that the battery is drained- just a couple of seconds before it plummets to the floor/ground or wherever you are flying it. All of the Hubsan models provide ample warning time that it's time to land by flashing their LEDs. The H107D indicates battery life on the remote. That said, the Blade does have a certain smoothness to the control algorithm compared to the Hubsan.
For my own indoor enjoyment, I have the smallest X4 H107L, the H107C (has on-board camera recording to micro flash just for fun), the H107D FPV (currently broken awaiting to hear back from Hubsan) and a Blade Nano QX.
All of them are fun and can help you learn to fly the Phantom better. I am less keen on the Blade though for two reasons- 1) price point is quite a bit more expensive than the base model Hubsan (even after adding a prop guard) and 2) there is very little warning that the battery is drained- just a couple of seconds before it plummets to the floor/ground or wherever you are flying it. All of the Hubsan models provide ample warning time that it's time to land by flashing their LEDs. The H107D indicates battery life on the remote. That said, the Blade does have a certain smoothness to the control algorithm compared to the Hubsan.