Diet Planners work on your suggested weight range, BMI and suggested calorie intakes, however, this varies massively from person to person which is why they are not too successful and can only be used as a guidline. Another problem is the time consuming manual input required in order to track the daily intake of food, especially as the age group we are aiming at are the elder generation who havent grown up with modern toys(internet, computers,PDA etc.). These packages also incure a monthly subscription ontop of the cost of the internet, which may not appear too appealing. http://www.startyourdiet.com/howitworks.htm
Instead of telling you what to eat with strict diets, some websites try to educate the users by offering alternatives, with recipes and indicating how much you should eat to what you do eat. These can actually lead to saving money as buying ingredients tends to be cheaper than buying processed or frozen food. http://www.weightwatchers.co.uk/index.aspx
There are a lot of theories about what to eat and which diets are the best, however, not many of them take into cosideration of allergy or health problems, which is vitally important with elderly people. Medication can also make a difference to the diet as some foods don't compliment your medication and can lead to making the client feel worse or have undesired side effects. http://www.freedclinic.co.uk/
With these sites come forum where expert advice is readily available, this obviously is included in the price however offers a valuable service that would be hard to implement in our device. Possibly a website for those who do know how to use the internet could be included, or a phone directory to important organisations that offer dietry advice may be a useful tool to include.