I just recently got a new violin (an electric one, in fact) after almost a year and a half without.
Something I have rediscovered, is my absolute hatred of tuning. What doesn't help, is that my ear is no longer quite so keen. So, I'm thinking of getting one of those spiffy tuners that tell you if you're playing the right note.
If someone could recommend me a decent, but more importantly cheap one, suitable for an electric violin, I'd be ever so grateful
I do like the look of the Korg CA-30, but I'm hoping for something under £10. So yes, please help.

any old chromatic will do but lights are good.
i bought an ashton for NZ$30 which is roughly 10pound. it will tune every note but does not play a pitch. its a guitar tuner so you can plug your electric into it as well as play a note.

im an american so i dont exactly know how much your currency is worth here in the states except that its worth more than our dollar lol. try looking for deals on www.swstrings.com they tend to have some specials and im sure you will find a good deal on a decent tuner

People say that electric instruments tend to focus more on the rugged sound, then the fine quality of the sound..
If you have a regular instrument i suggest that you tune that one first, and then tune your electric one...
Other than that,
YOUR LOSING YOUR EARS!!! (don't let that happen!!!)

My 8 year old daughter started to learn the violin so I wanted to get her her own tuner. I play guitar mostly, but also play cello and violin. I have used chromatic tuners for close to 20 years and love them. I can tune by ear, but many times its not a realistic goal. A decent tuner is a must. So I invested in a tuner that works off the instruments vibrations. I thought this would be great for a couple reasons. One is, its smaller than other tuners. The other is as I learned, if you can feel it, you can pretty well tune it. I looked around and ask people I knew what they liked best. Out of all the musicians I know, only 2 actually had this type of tuner, and unfortunately, both of theirs are way outdated and not even made anymore. So I had to wing it and trust the sales person at the music store, which can often be a costly mistake. And I feel this time it was. I purchased the more expensive choice, the Intellitouch PT-2 Tuner. About $40 dollars with tax. I can see why no one is using these tuners. You have to have them placed just right. You have to attack the string just right. You really cant tune with the tuner active. You have to tune, then check, then tune, and so on. With all my other tuners, you pluck the string, watch the needle as you tune and bring it up or down as needed. Maybe one or 2 times and your done. With the Intellitouch PT-2 you do it one little step at a time. Up a little, down a little , until its happy. Then I discovered something I really didnt like about it. Its not constant or actually in tune. I tuned my daughters violin, and then played for about a minute. went back to check it again for tune and it was out. So I tuned it to the Intellitouch. This time it didnt even sound right, so I put my old trusty Peterson Stobe tuner on and it was off by as much as a half in some cases. I used the Peterson and Intellitouch together, and they still showed differences. So I put the Korg tuner into the mix. It agreed with the Peterson, but the Intellitouch tuner was still off.
So I can say from my experience, Im not that impressed with the Vibration style tuners like the Intellitouch PT-2. Its over priced, not very easy to learn or use, and at least mine has the accuracy of a brick.
Your experiences may differ, but as for mine, Im not a fan of this tuner. I say , stay with the little bulkier but apparently much more trustworthy, accurate, and very easy to use peg and needle , or even LED or LCD readout chromatic tuners that work in real time. And by real time I mean you turn the peg or machine head, it responds accordingly and shows you were you are in the tuning.

There, my long winded, informative rant is over.
Hope it helps you some.

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PS. Edit
You mention the Korg CA 30. Yes, I have this one too. Its a very good durable and easy to use tuner and well worth the money. You wont go wrong with it.

The Korg CA 30 is probably the best of the smaller tuners. Its responsive, reliable and sturdy (I dropped mine quite a few times, until even the batteries came out. I popped the batteries back and it still worked perfectly well.) As a point for convenience, the Korg is the only tuner I've seen that remembers whether tuning was set to 442 or 445Hz. All other tuners reset the setting to 440Hz and I personally find that very irritating. ><

Some of my friends have tuners of other brands (mostly Intelli) and those tuners all take a very long time to respond, assuming it does. The tuner doesn't really recognise changes in notes as well and can be very inaccurate, as DadDan says.

Basically, just go with the CA30. Its worth it. But watch out for the ones made in China, they are a little 'too' sensitive. Mine changes notes even when I'm holding the same note the entire time! (Happens when other people play as well so its not just me ) I used to have two Japan-made tuners but I lost both, so I tune by ear now :p