I realise that this may not be the most appropriate forum for this topic but there's a lot of telephony expertise here and you might be able to help.

My partner's 95 year old father has had to move to a care home. While the home is very good about getting incoming calls to residents he would like a mobile, mainly to make it easier to keep in touch with his daughter and friends. I'd appreciate your recommedations for both phone and SIM.

Here are the requirements:

Ultra simple to use. He's a complete technophobe.
For phone calls only - he'll never use text etc
Loud ring and speech - he's a bit deaf
Big buttons
No button combinations to unlock
Charging by cradle rather than cable
PAYG rather than contract. Though c£5/month contract might be OK.
Topup online so daughter can monitor usage and top up.
Not too expensive. PAYG at 1p-2p/min would be fine.

There are some flip phone models by Doro that might work well. Just open the clamshell to answer a call, close it to hang up, no need for unlock codes.

TTPHONE are another company  that specialises in phones with  large buttons, clear large displays, and loud volume etc.

Might have something suitable.

http://www.ttfone.com/

Or how about a mobile phone in the form of a desk phone. You insert a mobile phone SIM card, connect to the mains power and use as a normal desk phone but the calls are made using the GSM network. Something like this i have seen Big Button ones advertised have a look on ebay.

http://www.gsmdeskphone.co.uk/GSMdeskphones/DPH500-GSM-Desk-Phone-and-GSM-taxi-P...

Note not all phones  take a 3g/4g sim some operate on 2g only. 

Other Pay as you tariffs you could  look at  other then three are  O2 new pay as you go 5p a minute tarriff

http://www.o2.co.uk/help/pay-as-you-go/classic-pay-as-you-go


and 1p mobile which runs over EE.

www.1pmobile.co.uk

On the contract front Plusnet Mobile runs on EE currently offers 500 minutes  30 day sim only

www.plus.net/mobile/plans/sim-only/

Or for £4 a month you can get 250 minutes with Carphones IDNET runs over Three.30 day sim only.

https://www.idmobile.co.uk/shop/plans/sim-only-deals?gclid=CKWdj9XH49MCFQoo0wod4...

Talkmobile Happy Hour sim lets you talk to mobiles and landlines for up to an hour for 10p.

https://talkmobile.co.uk/payg/payg-charges

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