I have just update my iPhone and iPad to IOS 10. I meant to have a sort out and a tidy before I did this, but you know how it is, a new toy and I can't wait so I am doing the housekeeping afterwards. As part of this I realised that you can combine the Reader function in Safari to save clean PDF versions of web page to iBook. For all of you familiar with these techniques that all there is to know, you probably knew any way. For anyone interested but do not know what I am writing about the read the following.
For the last few versions of Safari, both IOS and OS X, many web pages can be presented in a cleaner view by clicking the Reader symbol. This will strip out all the peripheral content such as adverts and comments.
This will transform the web page to the following
Share to iBook
If you click the share button, the little box on the right with an arrow coming out of it, you should be presented with various options to share this web page. The options presented to you will depend to a certain extent upon the apps you have installed. Assuming you have installed the free Apple iBooks app you can select the Save PDF to iBooks option.
You now have a clean PDF version in your iBooks which can be easily found again and even accessed offline. You also have the option to remove offline copy and just keep a copy in iCloud or delete from everywhere.