Fastest USB mains charger

Q : How fast can a USB mains charger be ?

Answer :
My ebay search for a 5v dc charger suggests a current output of 4500ma 

Standard specs for small device USB charger :
5v dc
current output varies up to 4500ma ?

The 5v DC stays the same so the current size will seem to make it charge quicker
My ebay search suggests the present typical current output sizes on 5v dc charger are :

current output :
500ma (slow)
1000ma
2100ma
4500ma (fast)

Device warning :
I'm assuing the device may have a limit to it's max. current so maybe some devices won't charge at 4500ma but the USB charger will probably just lower the current automatically.

Note : more devices connected divides the current
If your charger has 4 ports and 4 devices connected, current will be divided by 4

example :  
4 devices charging on 2100ma 5vdc charger
current to each device will be 2100/4 = 4 times slower to charge

My knowledge on subject :

sketchy 

USB mains charger : why does it slow ?

Q : Why does my mains USB charger take longer the more devices I connect ?

Answer  :
It divides the current between the number of things being charged.

Example
4 devices on a 2100mah 5v charger
current to each device = 2100/4 = 4 times slower charging

Can't open audioboom android app when offline

Audiboom android app

Q : Why can't I open the audioboom android app when offline ?
A :  It seems they are aware of this 'issue' and are 'working on it'. It means you can't listen to audioboom downloads through the app when you are offline

About :
Using  audioboom app in an android device OFFLINE.
When launched offline, the app says 'Uh oh! Looks like your network's cut out. Want to try again ?'. And you can't open it to get access to the downloads via the app.

Temporary workaround :
They say if you launch the app when you are online and keep it open, you can then access the downloads.

Perhaps the downloads are in an accessible folder somewhere in the android device, but I have not found the folder 

Can I charge my phone/tablet wirelessly ?

Q : Can I charge my phone/tablet wirelessly ?

Answer : You can if your phone/tablet  has the required QI wireless receiver inbuilt (note : this has nothing to do with 'wifi'). You would then buy a 'transmitter' for it and it should charge when near (note : this seems quite new technology. Many seem to complain of poor power charge). The technology seems to be known as 'QI'



Q : What if my phone/tablet does not have the QI receiver inbuilt ? Can I still charge it wirelessly ?

Answer : You can but you need to buy a QI receiver as well, and plug the receiver into the phone/tablet when about to charge. The receivers are very slim though (see video below about a 'retrofit')



My knowledge on subject : 3/10 and new

Comment :
This seems like charging by 'induction', the same as used by many electric toothbrushes (e.g. Braun). For phones/tablets it seems a new method of charging. I have seen reviews that said it hardly charged at all. Other chargers have got good reviews. Currently it seems mostly high-end phones that have a receiver inbuilt but I think over time it will become the norm.   

In summary :
If your phone/tablet has an inbuilt QI receiver : buy a QI transmitter and it will charge

If your phone/tablet does not have an inbuilt QI receiver : you need to buy a QI receiver and transmitter. The receiver will fit to the micro usb input of your device.

Possible problems with receiver :
Most receivers are designed for phones with the micro usb port at the bottom of the phone
You also need to check which way round the micro-usb port is (narrow side up ? narrow side down ?)

Links :
Check if your phone is 'QI compliant' (or if you need a receiver too) : QI Inside
Wikipedia : QI (inductive power standard)
QIwireless website 
How to add wireless charging to any device : QI wireless article 
Pocketnow articles : wireless charging

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Amazon links :

Amazon USA search : Wireless charger

Amazon USA search : Wireless charger receiver QI (for phones without inbuilt QI)

Amazon UK search : Wireless charger

Amazon UK search : Wireless charger receiver QI (for phones without inbuilt QI)

How can I listen to audio on Android with a Mono Bluetooth Headset ?

A Mono Bluetooth Headset

What I want to do :
Listen to audio on an android phone though a Bluetooth Mono headset

Problem :
My mono bluetooth heasdset is paired with my Android device but I cannot listen to music. It only works for phone calls

Answer :
You need an app from Google Play.
I am using free  'Mono Bluetooth Router' but there are alternative apps 

Instructions :
Pair up the headset with the Android device (e.g. phone/tablet)
Download an app via your Android device from Google Play (for me : 'Mono Bluetooth Router' )
Find the app icon on your phone. Click it and press 'connect'
If the headset and device are paired and you have bluetooth switched on, it should work  

Do stereo bluetooth headphones need an app to play on an Android device ?
Answer : I don't seem to need one. My stereo headset works fine and the sound quality is much better. 

Note :
The sound is very poor but it works. I might try other apps to to see if it's to do with the app but I think it's the headset that is the problem. 

It seems to be an Android quirk that mono bluetooth headsets need an app to play audio on Android devices. They work ok for phone calls though.

Which wireless remote shutter release for Nikon J2 camera ?

Question : Which wireless remote shutter release works with the Nikon J2 camera ?

Answer : ML-L3 Wireless remote control

The ML-L3 can be bought as an 'official' Nikon part for around $20/£15 or you can buy a 3rd party compatible copy for much cheaper    

The ML-L3 is listed by Nikon as compitable with a number of certain cameras in the Nikon ranges if they are infra-red compatible. The cameras would be certain cameras in the ranges Nikon D-SLR, Nikon 1 and Nikon COOLPIX (check your camera is compatible)

Important :
Check your camera has infra-red capability
Check the camera is compatible with the remote control (in this case ML-L3)  

Links :
Amazon USA search : ML-L3 (cheapest first )
Amazon UK search :  ML-L3 (cheapest first)

Nikon USA page on ML-L3
Nikon UK page on ML-L3

Braun Mobile Shaver M60 and M90 : What's the difference ?

Question : What is the difference between the Braun Mobile Shaver models M60 and M90 ?

Answer : It looks to me that they are the same except the M90 also has a 'trimmer' whereas the M60 does not.

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links :

Braun website : basic comparison of M60 and M90

Comment after 1 year use of Braun M90
I guess it's meant as an 'afternoon shadow' shaver so in that sense it does what it says (though it could cut even finer). It's a very 'fine' shave but not fine enough for me (still feels like I could get closer). It cuts well with no/little catching etc. On the downside it is just too fine for anything more than short growth (but not fine enough for a very close shave), though it will cut longer growth without catching (much)  (but takes a long time). It also seems to miss some stray long hairs which is irritating.    

It's a quality product though I prefer rotary foils for a close shave, but the rotaries I have used get too close and irritate my neck skin same as a manual shave.