Wednesday, November 21, 2012

hi4hi Muffler Privacy

100% Privacy!

hi4hi muffler doesn't uses the internet connection and hence it neither collects nor transmits any information outside of your device. The only information that goes out of your device is the SMS to the caller telling when your phone will come out of silent mode and that is a feature.

I will talk a bit about the permissions that hi4hi muffler uses and why.

The following permission are used to detect the caller and send sms. Sending sms can be disabled from the settings, in which case the app will ignore missed calls.

These are needed to know the number of the caller and send SMS when your phone is on silent mode.

The permissions below are all used for generating notifications. Notifications can be disabled from the settings. 

This is to check if received SMS is from hi4hi muffler. It can be avoided but the alternative will cost battery life.

This is required to show the name of the contact instead of the number.

These are needed to delete the auto-sms from the hi4hi muffler app to keep your messaging history non polluted.


hi4hi Muffler v2.0

This one was quick ;)
Added ability to read auto-sms sent by other muffler users. These messages are read and converted into notifications which show up exactly when the earlier called user switches OFF the silent mode. Moreover these notification are clickable and on click will dial the earlier called user.


  1. Launch Muffler. 
  2. Choose timeout.
  3. Done
If Caller calls Receiver when Receiver is on silent mode, he gets a sms with the time at which Receiver will come out of silent mode.
  1. Calls Receiver
  2. If Receiver is on silent mode, he gets a text message with time at which Receiver will come out of silent mode.
  3. At this point Caller doesn't even need to look at this sms. Muffler will read the message and create a notification which will show up exactly when Receiver comes out of silent mode. 
  4. Caller looks at the notification and clicks it to call the Receiver.
  5. Done

Monday, November 19, 2012

Muffler from hi4hi

My first Android App.  I often forget to change back to normal mode once I switch on the silent mode, usually during movies or meetings. This app allows me to choose a timeout of 10 minutes, 30 minutes and 1-2-3 hours after which the silent mode will be automatically disabled. It also sends an SMS to the missed callers with time at which my phone will come out of silent mode. This way they know when would be good time to call me back. It is possible to disable sending sms completely or to just sent it for people in your address book.

Install Muffler from android app store if you too forget switching back to normal mode. You can also search android app store for "hi4hi muffler".

Update  Added ability to create notification based on muffler smses. Basically if you call someone whose phone is on silent, the app will read the auto sms and create a notification which will show up exactly at the time that persons phone comes out of silent mode. Instead of you waiting, the app waits on your behalf and lets you know that now is the time. Moreover, the notification can be clicked to directly dial without going back to address book or call records.

Privacy  explained.

Monday, November 05, 2012

Stopping begging mafia

Begging mafia operate by kidnapping children and forcing them to beg. They give food to these children and take away the earnings. The ethical dilemma is that if you give money - you are supporting the business and if you don't children are going to starve.

One way to get out of this would be the use of food-coupons which expire. The begging mafia works because money intended for food or education can be used for anything. If we give food coupons to beggars they can buy food and only food with those coupons. If these coupons don't expire, they will become some sort of currency which can then be exchanged for money. By making them expire we insure that they are used for the purpose they are intended for. The expiry could be as small as today and as large as may be a week. We don't even need to print these coupons. It can be easily managed by a mobile app that gives you a number which you can write on a piece of paper and give to anyone you want. The person can give it to anyone who accepts this coupon, who can check if it is valid using his mobile, may be by calling or by sending sms. May be you can get these number before hand so that you can write them down/take a printout and just "activate" them when you give it to someone.