Interesting, but; I got an iphone 4 nearly three years ago (and it was old then), and it came with the 'torch' feature in the native firmware.
Is this warning really for android phones, or has Apple been installing malware in their phones?
OK, just found this;
http://www.howtogeek.com/198846/no-your-iphone-flashlight-is-not-spying-on-you/
Pretty much as I suspected, native iphone flashlight is safe.
Why would you download another?