关于双卡双待，你不知道的秘密

Group 1 - The article discusses the evolution and significance of dual SIM card functionality in mobile phones, highlighting its origins and the role of Chinese manufacturers in popularizing this feature globally [1][3][5] - The introduction of low-cost chip solutions by companies like MediaTek significantly reduced manufacturing costs, enabling the rapid proliferation of dual SIM phones [3][6] - The demand for dual SIM functionality in China is driven by factors such as varying telecom package costs, the need for separating work and personal numbers, and differences in network coverage among operators [8][10] Group 2 - The article explains the technical aspects of dual SIM technology, including the two main modes: DSDS (Dual SIM Dual Standby) and DSDA (Dual SIM Dual Active), detailing their operational differences [15][17][19] - DSDS allows both SIM cards to be on standby but only one can be active for calls or data at a time, while DSDA enables simultaneous use of both cards for calls and data [19][21] - The advancements in VoLTE and VoNR technologies have enhanced the quality of voice and video calls over 4G and 5G networks, respectively, improving the dual SIM user experience [23][25] Group 3 - The evolution of SIM card sizes from Mini-SIM to Nano-SIM has facilitated the physical implementation of dual SIM functionality in smartphones [29][30] - The design of SIM card slots has transitioned from fixed internal slots to more user-friendly removable trays, allowing for better space management within devices [30][33] - The emergence of eSIM technology represents a significant shift, eliminating the need for physical SIM slots and enhancing device waterproofing and user convenience [37][40][41]