[FAQ] About environment to use

• I don't have a smartphone, so I would like to buy one. Can I use a SIM-free mobile phone? Also, can I use it with a feature phone?
• Can it be used on an iPad or tablet?
• If my smartphone reaches its communication limit, will there be changes in sound quality or delays?
• Can I connect multiple BONX earphones to one smartphone?
• Can I have a conversation between an iOS smartphone and an Android smartphone?
• Is it possible to use apps while tethering?
• Can I connect an amplifier to the iPhone's earphone jack and output audio from the amplifier?
• Can it be used only with Wi-fi communication?
• What should I do if there is a place where I plan to use the service but there is a place where I am out of cell phone signal and Wi-Fi coverage?
• Even in environments where wireless frequencies such as Wi-Fi and microwave ovens are flying around, such as convenience stores, are there any effects on call stability or peripheral devices?