Using electrical appliances in England

For your Samsung7 and Ipad you don't need a converter just an adapter. If you look at your charger, it probably says 120/240v which means it's dual voltage.

If the hot rollers are only 110v then you will need a converter. If they are dual voltage you won't.

You can find more on this topic under the "Tips & Trip Reports" heading; choose "Technology Tips."

My Galaxy tablet did fine charging with just an adapter in England. Also the Kindle and the Canon camera battery and the cell phone and my wife's iPod.

I can't help you re rollers, if you could see my head you'd know why. ;-)

Read Rick's FAQ response regarding electricity: https://www.ricksteves.com/travel-tips/phones-tech/electric-adapters-converters

If your device is rated for 110 to 240 vac (volts alternating current) and 50/60 Hz, you are good to go with a plug adapter that allows your North American flat prong plug to fit the UK outlets. If your device is only rated for 120 vac don't bring it. Light weight voltage converters (240 vac input stepped down to 120 vac output) often cannot not handle sustained power even though they are nameplate rated for the designated amperage/wattage.

Make sure your hot rollers are duel voltage. I use these while in traveling and they work great. All you need is an adapter. https://www.amazon.com/Remington-Compact-Ceramic-Worldwide-Voltage/dp/B000EPJNMW/ref=pd_rhf_se_p_img_1?_encoding=UTF8&psc=1&refRID=1ZQA5VF7A63XRKP2MVBD

I find that hair appliances and converters are a recipe for disaster so dual voltage is a better way to go. These automatically adjust to the correct current (no switches to flip, or forget to flip). The heat quickly.

More info:
https://www.theroamingboomers.com/how-safe-are-your-electronics-in-england/

Make sure that if you buy plug adapters in the US that they are legal to use in the UK, they should be fused and the live and neutral pins should be sleeved, like this:
http://www.postofficeshop.co.uk/images/product/extraLarge/2/AA148_1_aL.jpg

Converters are heavy and take up lots of room in your suitcase. Many hair appliances do not work well with converters as they draw too much current and the result is a fire at worst or a blown fuse at best. It would probably be easier to buy a set of rollers once you reach the UK if you simply can't live without them.

Cell phones for the most part work fine with just the plug adapters. I know for a fact that the iPad (and other Apple products) are all perfectly fine using only a plug adapter as long as you are using the charger that came with it from Apple. The adapters sold by RS for $1 work perfectly fine for a low current item like a phone, iPad, and camera battery chargers.

Please be careful with the hot rollers, straighten irons etc - they do not work well even with a converter. I frequently travel to England to visit family and I have had many mishaps with straightening irons, they either don't work at all or they become a fire hazard. I have learned not to bother with taking my beloved straighter (but It's really hard to go without it).
If you can't live with out them - go to Boots (like Walgreens) and pick up cheap rollers for the trip. (I am pretty sure there is a Boots at the airport).

I bought my UK adapter at Wal-Mart here in the states
It worked perfectly for my hairdryer, kindle, phone.
The devices were all purchased in US and have our regular US plugs.
PS they are all dual-voltage as described above.