Nokia aka Microsoft is in the process of rejuvenating its smartphone line-up though the focus right now is centered more around coming up with specced up versions of the existing Lumia devices than launching completely new smartphones designed afresh from ground up. This is evident with the several Lumia devices seen so far carrying the moniker 530, 630, 730 and 930. Lumia 830 codenamed "Train" no doubt will fill the void between the last two. Also, all the devices mentioned here are spruced up versions of Lumia 520, 620, 720 and 920 with the Lumia 830 being the next gen version of Lumia 820.
However, there isn't a whole lot of information available of the upcoming Lumia 830 as of now, except that the device will be targeted at the mid-range segment, claims Neowin. Expect the device to be suitably specced which rules out the smartphone being a speed monster or having class leading features. Further, as Neowin's Brad Sams further mentions, the Lumia 830 is expected to be an AT&T exclusive.
Meanwhile, in what can be termed as another interesting development, Chinese search site Baidu has come up with another image purported to be that of the Lumia 830 but carrying the markings, 'Nokia by Microsoft'. Something of this sort was already rumored, as is claimed by GSM Arena though we now have the first conclusive evidence of things indeed shaping up that way.
Earlier, we have seen rumors of the Lumia 830 flaunting an aluminum casing coupled to a polycarbonate cover at the rear. The rumor as reported in Headlines & Global News further mentions of there being a rear black circular patch for the Lumia 830 that's a lot similar to the camera housing as seen on the rear of the Lumia 1020. However, the same for the 830 lacks a distinct bulge which could be attributed to a less elaborate camera setup, the site further speculates.
These apart, the leaked images of the Lumia 830 also reveal on-screen Windows Phone buttons in place of physical buttons.
Also, apart from the Lumia 830 codenamed "Train", other upcoming Lumia device include the low-end "Superman" and the flagship "McLaren", as reported in HGN.