iPhone 6(s) (Plus) battery life on 2G/Edge Internet vs. 3G, (4G?), LTE and Wi-Fi?

[virtuality]

https://www.apple.com/iphone/compare/

Scroll down to Power and Battery, section Internet use.

As I understand browsing on LTE is more power efficient in general, than 3G. Hence, you get more browsing time on the 5s on 3G. (I don't know if 4G is thing in and of itself, separately from LTE). The 6(s) (Plus) must have some next gen. mobile chipset if it offers the same browsing time over - the, said to be less efficient - 3G connection as over LTE. In case all my assumption about 3G vs. LTE power-efficiency and chips is correct.

Now, I heard you can browse the slow Internet over 2G/EDGE in an even more power efficient way (as compared to 3G, at least).

What if
- I am touring the 3rd world, without LTE (which might be the most power efficient connection, but I'm not sure), or, just an area with sparse LTE coverage,
- With only 3G and 2G coverage to choose from
- I don't need high data, just to get my notifications and the occasional chat

Is, or can 2G/Edge be more power efficient than 3G?
Is, or can 2G/Edge be more power efficient than 4G/LTE? Even in a developed 1st world city with good LTE coverage, assuming I have the above, low data needs.

Battery power is dear, esp. on iPhones, as you know.

 

[JeffMD]

No, the battery life is not a noticeable difference on todays chips. The underlying cause of battery drain when not interacting with the phone is primarily signal strength. I don't think the phones boost to much as long as it is able to easily get on a 3g/2g network. However if you hit roaming or no signal, power use goes way high while it searches for it's own towers.

Wifi/bluetooth have their own power save features and are also of little impact these days.

 

[Commodus]

These days, the biggest differences are between cellular of any type and Wi-Fi. You'll get more battery life with Wi-Fi as a rule. Cellular now depends more on the strength of the signal and how much you're asking the phone to do. If you're on a weak LTE signal where your phone has to work overtime to maintain a connection, that could be worse than a slow-but-reliable 3G link.

 

[postmortemIA]

2G generally has stronger signal than newer standards, so if your signal is weak you could save some small power but you're more likely going to waste more battery on screen being on... everything will loader slower on 220kbps

 

[JeffMD]

2g is being phased out, carriers like att are disabling 2g in the new year.

 

[JAG87]

With good signal strength, always choose the fastest connection available. The biggest power savings lies in racing to sleep.

Of course this holds no water if for whatever reason you have 1 bar of 3G signal and 5 bars of 2G/E signal. In that case, the connection (although a slower one) will be established a lot faster with Edge, and if you're not doing anything demanding that requires the radio to stay engaged for long (i.e. text messaging only), then the radio would likely return to low power mode quicker on 2G, and it will be the more power efficient connection. Not only that, but if you choose to keep 3G engaged, the radio will have to stay in a higher power mode to maintain connection through the weak 3G signal, and it will destroy your battery.

So like postmortem already hinted at, it all comes down to signal strength, and you won't really know until you are there on location.