Inconsistency in setting html text to Android TextViews and WebViews

I am using Html.fromHtml to setText to my textView. Here is my text.

The figure below is not drawn to scale. Which of the following will most likely to be the value of ∠P?

In this sentence, angle sign is html value (

It is working fine in emulator. I also tested on some android device (some unnamed tablets an ebook readers). They are ok. But in my android phone (Sony Xperia X8), it is not rendering angle sign. Instead, it is showing

Is there anything wrong? Why is it not being consistent across devices although it is just a textview rendering simple html? More importantly, how could I solve this issue. Following is my graphical representation of my problem.

Edit: It is not only in textviews but also in webviews. I changed using webview instead of textview. Unfortunately, it didn't work out as well. Anyone got any idea?