Recording of call in mobile phone

1. Privacy of phone calls is a complex topic. There are many nuances and unanswered questions. Below thoughts are based on my limited understanding. Others may please feel free to correct me.
2. Third party recording of calls is illegal in most situations.
3. For calls entirely within India, if only one party consents to a recording it is legally OK.
4. For international calls the stricter standard of privacy laws between jurisdictions needs to be respected. In several US states and EU countries consent of all parties is required to record a conversation. 
5. In India, call recordings are admissable as evidence whether obtained legally or illegally. Many foreign jurisdications do not allow illegally obtained recordings as evidence. 

there is no law in favour neither against it. under section 65B of evidence act, you can produce mobile recording as evidence. we have to be practical at times. if someone is criminally intimidating us over the phone, we would rather record the conversation and implicate him. we will face the consequences of recording without consent (if any) later.