Mobile Data sim ?

How long are you planning to test for? Figure a standard PAYG SIM with a 30 day bundle/pack would be enough for testing purposes. There’s no recurring payments unless you want to continue testing.

Consider Smarty it runs on Three network and it's a 30 day contract, so for for £10 a month I believe you can get 30GB-60GB a month depending on the offer or pay as little as £6 for only 4GB.

So why not just order a SIM and give it ago smarty.co.uk/ (edited)

Which network?

Three and EE do some with long expiry dates. You can get a 24GB SIM with 24 months to use it for example. But they tend to be quite expensive to buy.

The other option is to get one of the SIMs like o2 Classic pay as you go. 3p a minute. 2p a text. 1p a megabyte. If not using much data then it will just charge per megabyte as and when you use it. And not disappear after a month.

And finally. This does expire but it’s cheap. Lyca have their 1p a month 5G SIM card for the first 6 months and you can cancel anytime. It’s so cheap that I had to mention it as it may be a better option than paying stupid amounts for the likes of the above 24GB SIM.

A few months ago I picked up a Lebara deal that costs me £0.94 per month.
For that I get 12GB of data per month and unlimited calls and texts.
But I pop it into a mifi dongle and it acts as a backup should the public wifi go down at the weekly computer club I attend. The dongle is shared with others at the club, but touch wood we have never exceeded the 12GB monthly limit. But I do carefully monitor the usage.
I had a similar deal with Lebara before this current one, and hopefully there will be a new deal when this deal expires.

Thanks for the replies.. I'll take a look and see which will work out best for me.