I use PayPal Here. They usually have offers for the cost of the reader. Customers use the reader (not your phone) to enter their pin.
Accepts contactless, chip and pin, magnetic stripe and aside from Visa, Mastercard, ApplePay etc it also accepts American Express
Their fees are a little bit more than the other brands you mention, 2.75% although this can go as low as 1% depending on sales volumes, but:
Both you and your customer immediately receive an e-mail about the transaction or a text for the customer if they prefer it.
Payment goes instantly into your PayPal account and can be transferred instantly to your bank, so there is no waiting for the funds.
Telephone support 8 a.m. to 6.30 pm 7 days a week
You need a PayPal account for the reader, but this also means that you can remotely request payments by e-mail from the PayPal website without the customer present.
Umm, if you have a PayPal account and upload the app to your mobile, then you can request a payment via e-mail from the PayPal website using the app, if your customer has e-mail on their phone while they are standing in front of you. All they need to do is click on the link in the e-mail, fill out the online PayPal payment form and click OK. You and the customer immediately receive an e-mail if the transaction is successful and the funds are immediately in your PayPal account.