Realme unveiled its P4 Power this week, boasting a 10,001 mAh battery that sits just 9.08 mm thick and weighs 219 g—43 % thinner and 14 % lighter than a typical 10 k mAh power bank. To test its reverse‑charging claim, the team paired a fully charged phone with a nearly‑dead iPhone 17 Pro at 7 %.

The test began with 22 W flowing from the P4 Power to the iPhone. After ten minutes, the rate dipped to 19 W and the iPhone hit 23 %. At thirty minutes, power fell to 11 W, pushing the iPhone to 48 % while the phone retained 80 % of its charge. By seventy minutes, the iPhone reached 70 % and the P4 Power sat at 61 %.

These numbers confirm the P4 Power can fully charge an iPhone once, but conversion losses mean it falls short of a second full charge. For most users, a 10‑30 minute top‑up is practical, leaving ample battery for gaming afterward. Realme also touts an 80 W SuperVOOC fast‑charge that tops 50 % in 36 minutes, a feature the team plans to test next.