From Australia, mig33: I remember feeling very disappointed when I first used mig33 - unstable connection and complicated operations. Less than three months later, I saw news about it being financed with 13.5 million US dollars and became interested in it again. When I revisited it, I found many unexpected surprises. The latest mobile version (3.05beta) can be downloaded through the mobile phone: wap.mig33.com. After experiencing it, I won't say much about its integrated IM function, as it's not a highlight. Its email and cheap call functions are more practical. After you register an account, you will get an email address of your [email protected]. Afterwards, you can log in to mig33 directly to check emails. This email is pretty fast [you can also set it up for SMS reminders (0.1 yuan per message), which is equivalent to pushmail]; the call function is also quite cost-effective: domestic calls are 0.14 yuan/min, and the rates to many other countries are also low. Mig33 also has a company domestically, and recharging is very convenient.
If any friends are interested, they can use their mobile phones to log in to wap.mig33.com or log in via computer here.
Ps: This software requires binding to a mobile phone number during registration, so one registered name corresponds to one number, and the number cannot be changed under this account later; the SMS function is relatively expensive for domestic SMS, but it's still acceptable for international SMS, and the speed is good!