[HD2 Android NAND Development] sanos99:
HD2 battery consumption tests with tytung's CM10 v1.3a ROM

This post is dedicated to battery consumption in "sleep" state, from 100% battery to 50% battery.

The phone was left on a table running tytung's ROM and the folowing background apps:

- Battery Monitor - to monitor the levels of the battery and make screenshots

- Weather Services PRO - to monitor a phone having a nice clock on the home page

The SD card is a Sandisk class 10.

Several tests are made showing the impact of having your wifi/gps/bluetooth/SD booster/Android assistant enabled or disabled, one by one.

The screenshots come in pairs for each test, the first one showing the remaining capacity of the battery (%) in time while the second shows the consumption in mA during the same interval.

As soon as a new test is ready, it is posted in the table below and the screenshots for it are attached to the post.

The result is the battery life span from 100% to 50%, measured in hours and minutes.

A phone which will be used on a daily basis will have a battery life less than the one tested, just because of the display and the phone calls.

-------------------------------------------------------------------------------------------------

|tst # | batt. type | bluetooth | Wifi | GPS | SD Booster | Assistant | .Result. | Picture id.. |

-------------------------------------------------------------------------------------------------

|..1..| ..regular.. | ....off...|..off.| off.| .not inst. | ..off.... | 72h40min | Pic. 01 & 02 |

-------------------------------------------------------------------------------------------------

|..2..| ..regular.. | ....on....|..off.| off.| .not inst. | ..off.... | 67h00min | Pic. 03 & 04 |

-------------------------------------------------------------------------------------------------

|..3..| ..regular.. | ....on....|..on..| off.| .not inst. | ..off.... | 23h50min | Pic. 05 & 06 |

-------------------------------------------------------------------------------------------------

|..4..| ..regular.. | ....on....|..on..| on..| .not inst. | ..off.... | 26h10min | Pic. 07 & 08 |

-------------------------------------------------------------------------------------------------

|..5..| ..regular.. | ....on....|..on..| on..| .installed | ..off.... | 23h20min | Pic. 09 & 10 |

-------------------------------------------------------------------------------------------------

|..6..| ..regular.. | ....on....|..on..| on..| .installed | ...on.... | 19h20min | Pic. 11 & 12 |

-------------------------------------------------------------------------------------------------

|..7..| ..extended. | ....off...|..off.| off.| .not inst. | ..off.... |174h30min | Pic. 13 - 16 |

-------------------------------------------------------------------------------------------------

|..8..| ..extended. | ....on....|..off.| off.| .not inst. | ..off.... |169h40min | Pic. 17 - 20 |

-------------------------------------------------------------------------------------------------

|..9..| ..extended. | ....on....|..on..| off.| .not inst. | ..off.... | 39h20min | ............ |

-------------------------------------------------------------------------------------------------

|.10..| ..extended. | ....on....|..on..| on..| .not inst. | ..off.... | 39h10min | ............ |

-------------------------------------------------------------------------------------------------

|.11..| ..extended. | ....on....|..on..| on..| .installed | ..off.... | ........ | ............ |

-------------------------------------------------------------------------------------------------

|.12..| ..extended. | ....on....|..on..| on..| .installed | ...on.... | ........ | ............ |

-------------------------------------------------------------------------------------------------

*Wifi on means also connected to a nearby wireless router.

* tethering on means also having a client (my tablet) connected to the Wifi hotspot, without making traffic.

* GPS on: the phone was kept in house, satellites could not be seen by the device, in order to make GPS search for sattelites and thus consuming battery.

* SD Booster is set with a 8192 MB cache size.

Some discrepancies were observed concerning battery consumption. It is however normal for these discrepancies to occur since the phone's behavior is not predictable with a 100% accuracy.

Small deviations are generally acceptable as pertaining to the phone's behavior, while large deviations can be accounted to the peripheral's consumption.

Conclusions:

*The following conclusions are based on a battery depletion from full to 50%. For real-life values you might considering multiplying these values with a factor of 1.5 to 1.8, since people usually recharge their phones when there is 10-25% battery left.

1. Bluetooth battery consumption is not significant as long as there is no traffic (music, hands-free driving). It can be left enabled even without an end-device connected.

2. Wifi Enabled and linked to an access point reduces battery life to near half*. Use only when needed and do not let it turned on. Data traffic will deplete battery even faster.

3. GPS turned on but without visibility to satellites has a very small impact on battery. However, when used with an app that uses it intensively (like a driving map or a gps speedometer), battery consumption goes huge, depleting the battery in little time even when the phone is powered from the car plug.

4. SD Booster does NOT enhance writing speed nor reading speed, instead it reduces battery life by 3 hours*. Not recommended.

Sandisk Class 10 card tests:

- with SD Booster (8MB cache): Read 16.3 MB/s, Write 7.6 MB/s

- without SD Booster: Read 25.6 MB/s, Write 7.6 MB/s

5. Android Assistant consumed 4 hours* of battery life while the phone was sleeping, without any significant improvement. Not recommended.