When sourcing for iPhone compatibility, prioritize MFi (Made for iPhone) certification to ensure safety and long-term functionality. Key specs include USB-C Power Delivery (PD) support, ideally providing at least 20W output to enable fast charging for iPhone 12 and newer models. For capacity, 10,000mAh is the industry sweet spot, balancing portability with the ability to provide 1.5 to 2 full charges. Additionally, if targeting the latest models, ensure the inclusion of MagSafe-compatible magnetic alignment with a minimum of 7.5W to 15W wireless output.