MacRumors yesterday reported via The Wall Street Journal that Apple may now be looking into reports of the latest revision to the iOS mobile operating system, iOS4, running slower than intended on iPhone 3G.

As the site notes, forums everywhere are littered with comments from iPhone 3G customers simply describing how the action of installing iOS 4 has slowed their device down to a crawl – and I can somewhat vouch for the issue too, with my brother owning an iPhone 3G, I too have seen this issue first hand on a number of occasions.

The most common criticism is that the phone is slow after an upgrade. There are also many complaints that the phone drains the battery quickly and becomes excessively hot. Concern about general problems such as slowness and battery life on gadgets isn’t unusual, but using iOS 4 on the iPhone 3G seems to make the problems so bad that the phone is nearly unusable for some people.

A few days back now, we reported that tests conducted by @TheNextWeb showed the next revision to the mobile operating system, iOS 4.1 (which is currently in private beta), should solve some of these issues.

[@WSJ via @MacRumors]