Q. I have a new laptop, and when I synchronised my iPad with it for the first time I received a message saying that I had now used my fifth allowed device. Does this mean that I have a problem looming?

A. No! Apple permit any number of their handheld devices to be associated with a single Apple account, but limit the number of PCs or Macs that may use a single Apple account to access the iTunes Store to five. So, when you need next to use a previously unused PC or Mac with your Apple account you will need to do the following. Open iTunes (on one of previous PCs or Macs) and then click on the iTunes Store link. Now log-in to your Apple account. You will see an option to de-authorise all of the computers associated with the account. Select this, and then re-authorise the computers you will be using from now on by opening iTunes on them.

Q. I am deaf, and use a speech to text app called Dragon Dictation on my iPad to see what people are saying. I would like to boost the hearing range, and wonder if it is possible to use an external microphone with the iPad.

A. It is, but the cost may depend on the quality of the microphone required. There are two microphones that will connect directly to the iPad's headphone socket. Of these two, the iRig Mic Cast Ultra is the cheaper option at around £30 from http://www.thomann.co.uk/. The other, with better audio, is the MicW i436 at £70, also from http://www.thomann.co.uk/. If you need something more akin to studio quality audio, then you will need a standalone microphone plus a cable to convert from USB to the iPad's lightening socket. The cable will cost only a few pounds, but a suitable microphone - like the Yeti USB Microphone - will cost about £125, and is sold by stores like http://store.compub.com/.

Q. I want to play Scrabble online with a brother who lives in the US. We both have the official Scrabble app, but they appear to be incompatible!

A. Think of Churchill's comment about "two countries separated by a common language"! You are using the British English "dictionary", whilst your brother will be using the North American one, so I suspect that that is the cause of the problem. Try using the Lexulous online equivalent to Scrabble, which works in all browsers and is free. To play online with your brother, you will both need to sign up using your e-mail addresses.

Q. I have a Nexus 7 tablet which worked well until I upgraded it to Android 5 ("Lollipop"), after which it has slowed down and begun to freeze and crash. Is it possible to step back to the Android version that I was running: "KitKat"?

A. Well, you can but it isn't straightforward. Before trying that, check to see if there any updates for Lollipop that you might install; they may solve your problems. If that doesn't fix your problems, go to http://www.tinyurl.com/kvrbok9 for full details of how to step back the operating system. In outline, you will have to download KitKat, and some tools, to a computer, and use the tools to unlock your Nexus and "sideload" KitKat on to it.

Q. I have a 16GB iPhone 5S which can't download the latest version of the iOS operating system because it says that the device doesn't have enough memory. Is my only option to delete a lot things from it and put them back afterwards?

A. A lot people are, or will be, having this problem: major iOS updates can require up to 5GB of free memory to hold the download before installing it. Instead of deleting data from the iPhone, use iTunes on your computer. Connect your iPhone to the computer using a USB cable and, if doesn't automatically start, start iTunes manually. Then click on the iPhone icon top left of the screen, then Check for Update. (It may well offer the update automatically.) On the assumption that you have the 5GB of free memory needed on your computer, the download will be made, and your iPhone updated, through iTunes.

Q. An app on my iPad has stopped installing an automatic update and says that it is "waiting". How do I remove the app?

A. You need to sort this out since it may delay other updates. If you haven't already, restart the iPad and/or connect to a different wi-fi network. If that doesn't work, go to the App Store, tap on Updates, and restart the update. If that doesn't work either, then you will have to delete the app. Do this by pressing on the app's icon until it starts to wobble. Then tap on the x in the icon's top left corner. Then press the round button below the screen to stop the wobbling. You can now download the app again for free and install it. Note though that any settings and data for the app will have been deleted.

Q. I keep all of my contacts' details in a Blackberry Curve 9300 telephone, but I'd feel more comfortable if I also had them printed out. Is there any way that I can do this?

A. You have alternatives, but both involve a PC/laptop. The first option is to connect the Blackberry to a Mac or PC and run the Synchronize routine in the Blackberry Desktop Manager software, which is a free download from http://uk.blackberry.com. Having done that, follow the instructions at http://tinyurl.com/pw76ovb/ to export your contacts as a CSV (Comma Separated Values) file. Once you have the CSV file, use a spreadsheet to open the file and print the contacts. The alternative is much simpler, but more expensive. Buy Elcomsoft's Blackberry Backup Explorer software from http://www.elcomsoft.com/ebbe.html - currently £49. This was originally created for forensic scientists, and allows access to, and printing of, all data, not just contacts, from backups created by the Blackberry Desktop Manager.

Q. I have an elderly smartphone which runs the Windows 6.1 operating system. I have 3,500 contacts on it, and when I try to transfer these contacts to my new Android-based smartphone via my PC, over half of them are lost. How can I transfer the complete set?

A. That is an enormous number of contacts by anyone's standards, and will require an “industrial strength” approach! First you need to export your contacts to your PC using iMobileTool (currently on offer at c.£11.50). Next, log into the GMail account that you must have already to use the Android handset, but using your PC. Open Contacts by clicking on the arrow next to Mail in the top left of the screen, then select More, then Import. Once the contacts have been imported into GMail, open the GMail app on your Android handset and tap Sync. It will probably take sometime to download so many contacts to your handset! N.B. Don't forget that your contacts will no longer be on your handset's SIM card, but in GMail on the Internet, so any future handsets will also need to be synchronised with the same GMail account.

Q. I need to print some of the text messages on my iPhone. Is there an app that does this?

A. The short answer is that there is no way to print text messages directly from an iPhone. However, if you copy and paste them into an app - like Notes - then there are ways of printing them. The iPhone operating system includes a wireless printing technology called AirPrint, which allows printing from some iPhone apps, but the number of printers as yet compatible with AirPrint is small, and they are at the higher cost end of the printer range. If your printer doesn't support AirPrint, then rather than buy a new printer I suggest that you install Fingerprint 2 (runs on both Macs and PCs), which costs around £18. Run on a Wi-Fi-enabled computer, this will find any printer connected to the computer and make it available to any Apple device. It also allows you to transfer e-mails and other files from an iPhone to the computer.

Q. I bought a second-hand iPhone, and put my personal data into it. However, when it lost charge, it would not restart, so I have arranged to return it for a refund. I'm worried though that my personal data - such as Facebook login and e-mail details - could be read by another purchaser once the problem is resolved.

A. Once a new battery has been fitted to the iPhone, which is the probable problem, you are right that your data will be accessible. You would be better advised not to return it but to pay Apple to replace the battery. (Apple don't like you to do it yourself.) This will cost about £50, plus P&P if you can't get into an Apple store yourself. If you decide to stay with returning the iPhone, at least change your passwords for services like Facebook and your e-mail using your computer. Other data should have been wiped when the battery failed. For the future, I recommend too using a passcode, which you'll find under Settings/General/Passcode Lock on the iPhone. Then, if the handset is lost or stolen, any new user would be forced to restore to factory settings, erasing all personal data in the process.

Q. My son has tried to send me e-mails from his company-provided Blackberry mobile telephone, but I am unable to open them in Outlook Express, and see a message reading "No sender - no message". Am I doing something wrong, do I need to change a setting somewhere, or might his employer be blocking them?

A. I'd not heard of this before, but I've done some digging about. It seems to be a known problem - with no solution as yet - particularly for users of smartphones, so it is most unlikely to be anything to do with you, your computer or your son's employer. It must a fault at the mail server, which would normally point at the mobile network service providers, although given how Blackberry handle e-mail - securely, which makes them attractive to companies - and that the problem spans many service providers across several countries, this could also point at Blackberry, though they are fending off enquiries about the problem and referring people to the network providers!

Q. Want to be able to track your laptop, smartphone or tablet computer if it is stolen or missing?

A. If you do, there are several software products to help you do so. One of the best is Prey, which is available in both a free version adequate for most people's needs, or a paid for version with some extra features. The program works in the background unknown to the thief, sending information on the device's whereabouts, and what it is being used for, to either a control panel accessible via the Internet, or a pre-defined e-mail address. It is even capable of sending images from a laptop's webcam of the person using it!