What exactly is the business of mobile phones? Thank you, everyone.

There are too many services, including (full-time communication, family fun, GPRS traffic packets, mobile newspapers, mobile securities, color ring tones, multimedia messages, short messages, Fetion, unlimited music clubs, mobile mailboxes, Olympic mobile newspapers, morning and evening newspapers, group color ring tones, group V networks, directory managers, short color clubs, mobile phone maps, call forwarding, follow-up lines, caller ID and SMS receipt. Color number, call transfer, international long-distance call, domestic long-distance call, international roaming, three-way call transfer, caller ID, call waiting, holding, loss reporting when a mobile phone stops, mobile phone revival, transfer and renaming, card replacement, call hiding, WLAN, long-distance call to Taiwan, Hong Kong and Macao, roaming to Taiwan, Hong Kong and Macao, points plan, WAP, SMS billing, vehicle violation notice, mobile secretary, super SMS, convenience SMS, etc. Sanwei learning, creative greeting card show, lottery information inquiry, SMS banking, early morning sunshine, family doctor, happy breakthrough, news and weather, music channel, fashion channel, game animation, bell map download, mobile bookstore, movie channel, fortune channel, chess world, puzzle game, sports competition, other games, cross-regional network access, credit service, cross-regional card exchange service and global VIP club. Group messenger, group SMS, GPS mobile positioning, community SMS, group address book, deposit, delivery fee), but I personally think this service (10086 customer service hotline) is the most practical. I can't remember, but these are basically the same for companies everywhere. I won't write about the business carried out by some local companies.