Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: Does it have an on and off button?   If not is it strong enough to keep plugging in and out of the cig lighter?
Document: It worked well, but not loud enough. I bought a GOgroove Flex SMART X3 and they have corrected the loudness issue. The lack of an on/off button was also inconvienent since my 1999 Mustang Cobra leaves the cig lighter powered all the time. Also corrected in the X3.
Bluetooth is the way to go! Also the RF transmitter on this thing is so strong, that I can tune into a live station and it will overpower it! So when travelling, you really don't have to keep adjusting stations like my old hunk-o-junk one for my iPod.
Perfect FM Transmitter. Automatically pairs with my iPhone every time I get in the car without fail. Where I live every frequency had a little bit of a transmission on it, but this is strong enough to override them and give me a clear transmission of my iPhone.
It has a nice strong signal and thus have no static on my selected radio station. I have had no problems with the device. The only (minor) design issue I have is the plug is much longer than I expected based on the pictures. I wish it was 1/2 the length, that isn't enough to take away a star.
Works awesome. Connects to my smartphone with a push of a button. Excellent sound quality. I always keep it on 89.7 and it never fails.
Because GOgroove doesn't remember your volume level. And a lot of times when I use it, I have to turn my volume up to level 25-30. To hear a decent sound to my ear. Specially if I use it to make a phone call.- Keep adjusting the device because of sound balance. The sound goes to only one side. So you have to adjust the device from your cigarette lighter to balance the sound that's coming out on your speakers.Me and my gf still use it.
It's collapsible and fits easily in your coat pocket or travel pouch. As I stated above, the only drawbacks I can point to is the absence of a power button and limited flexibility. As long as the device is plugged in and has power it is "on". You have to remove it from the outlet if you want to power it down. This can be a bit of a chore in itself since the SMARTmini has four VERY stout springs to keep it in place once plugged in.
I have been using this for a while for my car with iPhone5 and it works well. The only thing I need to do is keep changing the button to Aux mode from USB mode to receive incoming calls to connect to the speakers. I am not sure if this is specific to my car stereo. Plastic body could have been a little more sturdy. Otherwise, a great product and value for money.
I would have liked to have tried the option of connecting the cable from the device to the radio, but my radio does not have an "aux" input. Another thing to be aware of is that if you have a manual transmition and your "cigarette lighter" is close to the stick, you can knock the device enough to move the microphone (so that your caller can no longer hear you) or even knock the device out of the socket, effectively ending your call.
I looked this combo up and low and behold there were a number of them available! I wanted a small device without the cabling or gooseneck extentions so I took a chance on this GOgroove SMARTmini. I can't say enough how impressed I am! The device is always powered up in my car's lighter, it's small and out of the way, it connects to my iPhone when I get in the car, it's ergonomically sensible in it's layout, and it sounds good!!
Answer: My 2012 Chevy Impala does not shut off power to accessories so I purchased a 12-volt Power Adapter with on/off switch at Radio Shack. Plug my GOgroove into that and can keep my GOgroove in place at all times. Just switch off when I'm finished.