Which? has accused manufacturers including Apple, Google and Amazon of charging way over the odds for tablets with higher memory capacities.
A father whose son was murdered in 2009 has succeeded in getting Google to remove an image of his corpse from its map application.
These are dramatic new steps which will make the internet safer and better for children, a leading Internet safety expert writes.
Microsoft's Nicola Hodson said online child abuse content is "an evolving problem", making it "difficult to say whether anyone has done enough".
Ms Hodson told ITV News: "There is always much more to do, so we welcome the focus and we will continue to work hard on this area.
"We're very, very passionate about keeping children safe".
Prime Minister David Cameron admitted there is "still more to be done" to remove child abuse images from the internet, but stressed "huge progress" has been made.
Speaking after a summit at Downing Street, Mr Cameron said: "It's worth remembering we were told that cleaning up searches when people search vile terms, we were told it couldn't be done and we were told it shouldn't be done, for reasons of free speech.
"Well, we're now being told by the industry it can be done and it will be done."
Google's head of communications in Europe said there is "more that can be done" to prevent child abuse images being accessed online via search engines.
Asked why it had taken Google so long to tackle the child abuse content available, Peter Barron told ITV News social affairs editor Penny Marshall, "We have been working on this for many years".
"We've taken proactive action to identify this material online and remove it and report it, but there is more that can be done", he continued.
"Over the last few months we've had around about 200 people working on this to find new ways to deal with the problem".
Child protection expert Mark Williams-Thomas said the Prime Minister should be clear that today's announcement is more about stopping children and young people accessing child abuse images "rather than tackling offenders accessing this material".
However, Mr Williams-Thomas acknowledged on Twitter that it was "a good step forward":
The announcement this morning by the PM that Google will introduce key word filtering & video DNA is a good step forward.
2 key distinctions-PM focus is more abt stopping children/y.people accessing child abuse images . Than tackling offenders accessing material
It is good that children/y.people are a focus - but this is what the PM should be being clear about. Less spin PR more clear strategy
Microsoft said "increased collaboration" is key to combating online child abuse content, adding, "We need to tackle the core problems of creation, distribution and consumption".
A spokeswoman said: "Microsoft has long been focused on disrupting child sexual abuse, including developing PhotoDNA to strike at the heart of the repeated sharing of the same images time and again across the web.
"Increased collaboration between Microsoft, the Government, CEOP, the IWF, Google and others in the industry is the best way to combat this vile content. Today is a good step forward in this combined effort".
Campaigners have warned that a crackdown by Microsoft and Google on internet searches for child abuse images will not stop paedophiles using the web to share photos and videos.
Shaun Kelly, head of safeguarding at Action for Children and a member of the UK council for Child Internet Safety said: "This is a positive leap forward in the fight to keep children safe online.
"However, we must ensure that this level of work is maintained and remains at the forefront of internet protection".
The NSPCC has welcomed Google and Microsoft's decision to block images of child abuse via their search engines, but emphasised, "We must keep one step ahead."
Peter Wanless, chief executive of the children's charity, said:
Each image is a crime scene where unspeakable abuse was committed.
As sex offenders get ever more technologically advanced in pushing their vile trade, we must keep one step ahead and this requires a concerted and sustained effort from all quarters.
This is the key child protection issue of a generation - we cannot fail.
Labour leader Ed Miliband has welcomed the Government's deal with internet providers and search engines to block abuse images.
Mr Miliband told Daybreak, "Anything that can be done to protect children is really important".
"As a parent I really worry about what my kids have access to ... I think it's good to be taking action to protect our kids," he added.