Apple's new iOS 15 operating system is compatible with all of the iPhones that are able to run iOS 14, including the original iPhone SE, the iPhone 6s, and the ‌iPhone‌ 6s Plus.

Apple's list of compatible devices confirms that ‌‌iOS 15‌ works with all of these iPhones:

• All iPhone 12 models

• All iPhone 11 models

• ‌iPhone‌ XS

• ‌iPhone‌ XS Max

• iPhone XR

• ‌iPhone‌ X

• ‌iPhone‌ 8

• ‌iPhone‌ 8 Plus

• ‌iPhone‌ 7

• ‌iPhone‌ 7 Plus

• ‌iPhone‌ 6s

• ‌iPhone‌ 6s Plus

• ‌iPhone SE‌ (1st generation)

• ‌iPhone SE‌ (2nd generation)

• iPod touch (7th generation

As for iPadOS 15, it is compatible with a wide range of older devices:

• All ‌iPad‌ Pros

• ‌iPad‌‌ (8th generation)

• ‌iPad‌‌ (7th generation)

• ‌iPad‌‌ (6th generation)

• ‌iPad‌‌ (5th generation)

• ‌‌iPad‌‌ mini 5

• ‌‌iPad‌‌ mini 4

• iPad Air (4th generation)

• ‌iPad Air‌ (3rd generation)

• ‌‌iPad‌‌ Air 2

iOS and iPadOS 15 are being provided to developers starting today, with Apple planning to release a public beta in July.

Source: Macrumors