Tell the app this is OK to do.
How to enable the 'download using mobile data' feature on Spotify?
How to Download Music from Spotify to iPhone for Free- Tunelf
Spotify 101: How to Save Cellular Data When Streaming Music on Your iPhone or Android Phone « Smartphones :: Gadget Hacks
Spotify 101: How to Save Cellular Data When Streaming Music on Your iPhone or Android Phone « Smartphones :: Gadget Hacks
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iOS 7 Beta Tidbits: Per-App Cellular Data Usage, Live Clock Icon, Panoramic Wallpaper and More - MacRumors
How to download music and podcasts from Spotify
How to Download Music From Spotify
Grouping 5G and Wi-Fi together in Audio Quality is by far the worst change I've seen in iOS 15. On Wifi I have a DAC and no worries about data use. I'd
How to Disable Mobile Data for Spotify on iPhone
Spotify: Here's How to Download Content Using Cellular Data
Enjoy More Ways Than Ever to Use Spotify on Your Apple Watch—Now With Downloads — Spotify
How to download music and podcasts from Spotify