If you have a newer Samsung Phone, the &quot;Ultra Power Saving Mode&quot; is absolutely insane great!<p>The phone will standby for 20 some days, able to take SMS or a call the whole time, on a full charge.  Light SMS use will not impact this much at all.  I&#x27;ve used this on occasion to stay mobile for about a week on one charge, using the phone for SMS, light Internet and some calls.  Was curious just how far one could stretch something like this.<p>In this mode, BTW, Chrome will still do a lot of things, such as play mp3 files, view many documents, can access a browser e-mail portal, and so forth.  Most of the phone is disabled, but you still get SMS and calls, in addition to Chrome.  Be sure and make a link to your data directories in advance, so it&#x27;s easy to nav the filesystem in Chrome.<p>They missed some things:<p>1.  Airplane mode.  Use it to go long stretches, or to rapid charge off other devices.  This is also very useful when connections are spotty.  The phone will spend energy seeking networks.  If you know where to get a connection, airplane mode helps a lot when you know you are not where there is a connection, or you don&#x27;t need one for a stretch.<p>2.  Turn off bluetooth and wi-fi.  You probably won&#x27;t need either of those, if you really need a phone.<p>3.  Turn off advanced features, such as &quot;keep screen active when I&#x27;m looking at it&quot; kinds of modes.  You can use the power button to toggle this and manage the use of the screen down to bare minimums.<p>One example might be, turning off your lock screen, so the phone is just active when you want it to be.  This is CPU and display time you could use for a call, so ditch it for a little while.<p>Making a call means, tapping screen or power to access the GUI, initiate the call quickly, on your first ring, tap power to kill the screen, and you complete your call on a dark phone to maximize the battery savings.<p>4.  On some phones, a power on can take as much as a few percent of the battery capacity.  Measure this now, and you can balance standby techniques (airplane and low power type modes) with operating the phone at important times.<p>You may find turning the phone off to be a good balance.  It&#x27;s not on my device, due to how crazy good the &quot;Ultra Low Power Saving Mode&quot; is.  My older Moto Droid consumed 4 percent on restart.<p>5.  This one may be difficult, or unavailable, but there are apps out there to manage the radio too.  You can put the thing in simple &quot;1x&quot; data mode, no 3G &#x2F; 4G, etc... and get longer calls on less power, depending on a lot of things.  Doing this on the Note phones doesn&#x27;t make sense, particularly the newer ones that have aggressive power savings, but it did matter on my Moto Droid phones.  Mattered a lot.  This will limit you to first gen data, which is basically dialup modem type speeds, SMS and calls, but some phones also run considerably longer.<p>6.  If you can&#x27;t disable advance things, like &quot;pocket detect&quot;, just don&#x27;t carry the thing around.<p>7.  All of the monitoring type functionality, like &quot;OK Google&quot; consumes power too.  Ditch it where possible.  Often, a power saving mode does this for you.<p>8. Keep the phone temp near average, &quot;normal&quot;  A power on when the phone is cold will take more of the battery than when it&#x27;s all normal, room or body temp.  This can matter when you are down to that last few percent and need to make one more call.  You&#x27;ve shut it down at say, 5 percent.<p>If you turn it on when it&#x27;s really cold, the phone may see  3 percent, for example.  It might start up, then shut right back down, or only operate for a short time.  Warm the phone with your body, then attempt this for a bit longer run &#x2F; call time.  Battery potential varies by temp.<p>9. Do your testing and charging now.<p>I like to explore this stuff when I get a new device.  I&#x27;ll do &quot;stretch&quot; times just to understand what the dynamics are.  Sometimes, I&#x27;m off in remote places, or things happen.  Both of those are not the time to be working understand how this all works for you and your phone.<p>10.  If you can remove the battery entirely during long &quot;save the phone stretches&quot; do it.  Some phones continue to sip at the battery when powered off.  Be sure phone and battery are as warm as you are, when you do want to power that phone back up.<p>11.  Automatic brightness may be a savings too.  Turn it off, then set the display to it&#x27;s minimums.  You can always find some dark to use the phone.  This can be a very significant savings.<p>12.  Turn off location, etc... unless you may need it, and when you do, turn it on then.<p>13.  Consider learning how to turn the phone on in safe mode.  This generally does not launch power hungry apps.  It can be a lean way to operate the phone for a long no power stretch.<p>14.  It&#x27;s all about priorities.  Everything costs something, and you want to maximize the phone functionality you need.  This is written with the assumption that priority is calls and SMS.