In the first place, high functionality consumes power, but "battery life" is often cited as a complaint from smartphone users. Manufacturers are taking measures such as installing large-capacity batteries and providing modes to reduce power consumption, and I think that it has been considerably improved. It seems that many people are taking measures such as carrying a mobile battery.
In addition to such everyday measures, Samsung has installed in the "GALAXY J" an "emergency long-lasting mode" that can overwhelmingly reduce power consumption. It is a function designed for Japan, which is prone to disasters, and it is said that the battery of the smartphone will last longer so that you can contact even if there is a power outage. If you set this mode, the battery is said to last for more than a week. So far, I don't have a scene to use it, but I wanted to know properly in case of an emergency, so I tried it.
"Long lasting emergency mode" can be selected and set by pressing and holding the power button. In order to reduce power consumption overwhelmingly, the display is monochrome, and email and application notifications are turned off except when the screen is activated. From this cleanliness, the impression that "I will have it". "Dial", "Contacts", "SMS", "Mail", "Disaster Kit", "One Seg", and "Browser" are limited to these seven functions that are supposed to be used in an emergency.
These 7 apps (actually monochrome display) can be used by default. Only 2 apps can be added (actually monochrome display) While watching 1seg, horizontal display is not possible to save power even a little. There is no color, so I can't tell the Watch at a glance
And you can set up two messaging apps or social networks that you can use to contact you in case of an emergency. It seems to be a specification to select from a limited number of apps. I chose "Camera" and "LINE" this time. "LINE" and "Twitter" can be selected if the application is installed on the smartphone. However, "Skype" could not be selected even if it was installed.
By the way, even if you take a screenshot or take a picture, the saved data will remain color data, not black and white. You can clearly see that the display will only be monochrome.
Neither LINE nor the monochrome camera can take monochrome monochrome photos, and the data actually taken is in color emergency long-lasting mode, but the strobe function is not controlledTo cancel the "emergency long-lasting mode", I have to reboot. Some people may find it a bit cumbersome, but it's not a big deal. "GALAXY J" completed in about 30 seconds.
In this way, the energy-saving effect is due to thorough functional restrictions, but after using it for a while, I don't feel like playing with my smartphone. Normally, I tend to fiddle with my smartphone for things like internet, games, and SNS, even though I don't have anything to do with it. Is it because the screen is monochrome and dark? It's similar to the strange feeling of not having an appetite, and it's natural if you don't operate your smartphone, but it saves power. Even if you can play Puzzle & Dragons, it's monochrome, so you can't match the colors of the drops, and it might not be the time to play in the first place...
In the past, it was monochrome and the screen was small. I felt that it was a function that I would definitely like to use even in an emergency that is common.