can it be one color i would like to know if it can be set to purple?

Yes, it can be set to a single color, including purple.

Questions & Answers: RGBICW Smart LED Corner Floor Lamp 41'' with Music Sync, App & Remote Control, Color-Changing Ambient Lighting for Living Rooms, Gaming, Home Office

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RGBICW Smart LED Corner Floor Lamp 41'' with Music Sync, App & Remote Control, Color-Changing Ambient Lighting for Living Rooms, Gaming, Home Office

Smart APP Control: Easily connect and customize lighting via the Tuya Smart App with just a few taps
Remote Controlled Convenience: Easily switch colors, adjust brightness, and control effects from the comfort of your seat
Fully Adjustable Settings: Customize brightness levels and transition speed to suit your environment
16 Dynamic Color Modes: Choose from built-in presets or create your own custom color combinations to match any mood
Music Sync Function: Lights react to the rhythm of your music for immersive party or gaming experiences
Durable & Sleek Design: 41" height with a modern look that fits perfectly in corners or behind furniture