@Lloyd N8N - I recommend Highrise as a very simple and intuitive CRM.
It's one of the earliest cloud CRM solutions, and it is backed with good support. I've sent a few of my clients towards it. I have personally used it (but currently have no use for it), and my clients are happy with it.
I have no commercial links with Highrise (or any of these) whatsoever.
Runner up:
Insightly - this is worth looking at too. They have a great integration with gmail.
I have also tested (not exhaustive, but these are the big names):
Zoho - nice but tries to suck you into the entire Zoho eco system
Pipedrive - excellent for driving sales teams)
Salesforce - sledgehammer for a walnut),
Base - nice but extremely pricey
Capsule CRM - couldn't stick with it beyond the trial. although this was some years back.
HubSpot CRM - they've recently launched this as a 'freemium', it could be of value and is worth having a look at.
HIGHRISE PRICING DETAILS:
Free Plan: 2 users, no files, 250 contacts
Basic Plan ($24/month): 6 users, 5GB storage, 5,000 contacts, 10 deals