I found there are a few type of people willing to buy apps in google play in my circle of friends.
First of all, they are local australian , not Hong Kong people. They are happy to spend some money in good app. Most of Hong Kong people are still thinking android apps have to be free. Well ,there is no free lunch in the world.
Second type is ex iphone user. They get used to buy apps in appstore. Paid app is nothing strange to them.
Third one is business users. If they will buy any app which can increase their productive or earn money, they are very willing to buy those apps.

If you want to build some paid, you can target those kind of people

Recently, Whatsapp need to charge some of their android clients. As an Android developer, that is not a bad things. Most of android client ever bought anythings from Google Play. I believe there will be a number of users need to enter their payment details. After that, if they want to buy other paid app, they just need to click and their password again. That is easier. Moreover, after their first times to buy a paid app, they may think that is not too bad to spend one or two dollars for buying an app. That is good for us.

I upgraded my Galary S3 to Android 4.1.2. After that, I found there is a side bar on the screen, that sounds a Windows Desktop on my phone. That is good to have some short cuts like this. But that is too little. I don't like it much. I don't think that is useful for a Phone UI.

If you are in the field of photo editing, then you should know what is HDR Effect. In a simple term, this is a photo editing effect to make the photo more artistic! Sometimes, I use the copies of same photo to build a HDR photo in GIMP. Nowadays, there is a quicker way. There are some app make to do this job, such as an app calls HDRCamera in Android Market. You just need to open this app and then press a button to take photos. Just like your default android camera. Then it will do the job for you.

That is a quite good!

Finally, i bought an iPad for my company. First of all, the size and weight. That is not too heavy to bring and too small to use. That is a perfect size to bring around. Also, that is bigger than iPhone. This form factor is more suitable to use productive apps, such as time tracker and accounting software. Plus that is very thin too!

In addition, the soft keyboard is very good and responsive too!
Moreover, although the screen is not retina, that is still very sharp. You can have a look on the photo above. Lastly,for battery life, it can last for a week.

Well, there is only one weakness. It uses lighting cable. That is different from other iPad. As far as i known, not many accessories support that Overall, that is quite good.