I worry about air pollution especially when I'm in Jakarta or Singapore so I bought the Dylos DC1700 air quality monitor.
It is great to know exactly how bad the pollution is and how effective my air purifier is - I feel like I'm walking around with x-ray vision.
Sorry I don't know anyone who sells in Jakarta. I purchased it on Amazon.com and used the myus.com service to forward it to me. It's expensive but worth it for my health.