2013-14 Term 1 G2 TEO JIE TING A2

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  • Brief: Change
  • Activity: Splitting bills after a meal together with friends
  • Explanation: Eating out with a group of friends and family is always a fun and enjoyable thing to do. However, the headache usually comes when it is time to split the bills among everyone. Hence, my objective is to observe how people proceed with splitting the bills after their meals and determine what problems they faced while doing so. Through the observations, I hope to be able to design an application which change the way users calculate their bills after every meal.

Observation Notes

Participant 1 :: Geoffrey Goh Koon Hui

Ramen Play: 3rd September 2013, 11:00am - 12noon

  • Paid for the total bill
  • As everyone ordered different dishes, he need to split the bill based on what they ordered and taxes.
  • There were special orders (eg: 1 side dish was shared among 2 out of the 4 diners and 1 side dish shared among all.)
  • Calculated the bill manually (using rounding off) with friends.
  • A little disagreement regarding the calculated amount.
  • Has to calculate again to ensure final calculated amount is agreeable among them.
  • Friends either pay on the spot or pay at a later time.
  • Does not jot down the amount each friend has to pay. Based on his memory instead.
  • Admits that it's hard to remember who has not paid and how much was he supposed to receive.

Jieting Assignment2 Participant1.jpg

Participant 2 :: Lee Xiang Rui

Makisan: 4th September 2013, 11:10 - 12noon

  • Ordered 2 different servings of food which are priced differently to be shared with 2 other friends.
  • Had special orders (eg: topping up more to change from Hot Green Tea to Cold Green Tea)
  • Calculated the bill using calculator application on phone as amount is hard to be divided by 3 people.
  • Since amount to pay per person is not in exact dollar, he tends to take the amount to pay value as the lower dollar. (Eg: if the amount to pay is $4.30, he will calculate as $4.00)
  • As he does not have an exact change for his friends, he did not take the amount from his friends.
  • Says he don't note down how much each friend has to pay and tend to forget about it after a while.

Jieting Assignment2 Participant2.jpg

Participant 3 :: Zhong Jiahao Jeremy

The Soup Spoon: 4 September 2013, 4:26pm - 4:55pm

  • Ask his friend for the dish he ordered.
  • Calculate the taxes for the friend and ask him to remember his own tax to pay.
  • Ask friend to add the tax to pay with the cost of the dish ordered (without taxes).
  • Friend forgets what is the amount of tax he has to pay, hence resulting in inaccurate amount calculated.
  • Takes a while before getting the correct amount to pay (inclusive of taxes) for each of them.
  • Friend paid straight away.
  • Says that it is tedious to calculate taxes for respective dishes and adding up with the original cost of dish again, especially if there is a huge group of friends as he has to key in the cost one by one to calculate.

Jieting Assignment2 Participant3 1.jpg

Jieting Assignment2 Participant3 2.jpg


The participants I observed has varied ways and habits of splitting the bills. All of them does not know the exact amount, with taxes included, that everyone requires to pay without having to use estimation or the help of calculator on their phone (P1, P2, P3). The bill splitting process is made worst when there are multiple special orders and the bill is long (P1, P2). As some of their friends pay later than the others, they tend to forget who has not paid and the amount they need to pay after a while (P1, P2).

Problems and Solutions

Brainstorm partners: -

Problem 1: How much does my friend owe me?


  • Participant(s): P1, P2
  • Goal(s):
    1. Remembering the amount each friend has to pay after a period of time.
    2. Ensure that amount to pay are remembered accurate to prevent friend from over/under paying what they need to.
    3. Help to remind friends to pay for participants who are shy to approach friends for money.

Although P1 and P2 are the only two participants who faced the problem of friends paying at a later time during observation, P3 also expresses similar concerns about having friends that decides to pay at a later time due to various unforeseen reasons and both parties would ultimately forget about the amount to pay or forget about it completely. All of them admit that they need to jot down the amount everyone has to pay but feels inappropriate to do so when their friends are around.

Potential Solutions

  1. Ideally, a reminder can be sent to friends to remind them about the bill after a certain period of time.
  2. Have an application that keeps track of everyone's amount to pay automatically and create a reminder for everyone, irregardless of the payment status.
  3. An application that allows users to jot down which friend has not paid and the amount they are required to pay without the friends knowing. Application can be masked behind a fake application. (eg: the application can be masked behind a messaging application and friends would think that user is messaging someone)
  4. Have an application that creates a list that stores the friend's name and the amount to pay on the user phone. User will then remind them personally.
  5. Integrate with popular to-do application (eg: Google Task) to add payment as one of a to-do task.
  6. Have an application that constantly do a live-update of everyone's payment status and amount.

Problem 2: How much does each person has to pay?


  • Participant(s): P1, P2, P3
  • Goal(s):
    1. To calculate the exact amount each diner has to pay, taking into account the taxes and any special orders by individuals
    2. To get the exact amount in a fast and accurate manner.
    3. Amount calculated has to be agreeable among the rest.

As everyone has their own unique ways of splitting the bills, there may be some disagreement to how a bill should be split. This problem is even more obvious when there are special orders made by certain individuals in the group.

Potential Solutions

  1. Have an application that allows users to choose the method (eg: split the bill evenly among everyone, calculate taxes payable for each dish ordered and add in the cost of the dish..) they want to split the bill by and calculate the amount that each diner has to pay.
  2. Use Siri/ Voice command to do a calculation by reading out the bill. In this case, users will have to read out each amount and inform the Voice Command the number of people to split the respective amount by. (Eg: User will tell Voice Command "$10.50, 2 persons" and the Voice command will reply "$5.25 each")
  3. Have an application that stores more than one calculator screen in it so as to allow users to do intermediate calculations to get the final exact amount. This will save the trouble of users having to remember the amount returned at every intermediate steps thus reducing inaccuracy.
  4. Have a personal bill splitting application on every users phone. Users just simply have to key in the amount they are supposed to pay (inclusive of special orders) and the application will do a calculation automatically (inclusive of taxes based on default location set in phone).
  5. Have an application that is built on top of the existing calculator application in the phone where the application will do a step by step bill breakdown explanation.

Problem 3: Does the total bill tally?


  • Participant(s): P3
  • Goal(s):
    1. To ensure that the total amount received from each diner will tally with the amount stated on the bill

P3 has the habit of calculating the taxes payable first for each individual, inform them of the cost of their respective dishes and then asking them to do pay the amount summed from the taxes payable and the original cost of dish. However, amount received may not tally with what is stated on the bill as some friends may have forgotten the taxes they are supposed to pay. Calculation usually has to be done again on either P3's side or the diner's side. Usually it will take a long time and it does not seem nice having the waiter wait for the bill to be split.

Potential Solutions

  1. Have a calculator application that rounds up the total bill to the nearest dollar value (eg: $20.10 will be calculated as $21) and split it evenly by the number of diner. The change receive back will then be split evenly by everyone again. This will make sure that the bill is split in the quickest way possible.
  2. Manually write down on a piece of paper the amount to be paid by each individual. Upon receiving the amount from each individual, record on that piece of paper. Once all has been collected, verify if the total bill tallies.
  3. Make annotations on the receipt itself for each individual. Likewise to the above solution, tally the total bill against the total amount received.
  4. Have all the diners take a photo of the receipt and do the calculation of the amount themselves. Pass a piece of paper around for everyone to write down their name and the final amount to pay. Tabulate the total amount written down and ensure that it matches the amount stated on receipt.
  5. Have a simple cloud based excel sheet which allow diners to do a calculation of their own bills. One of them would just have to check and ensure that the total amount summed matches the one on the receipt.


Inspiration 1: reminder function on phone

  • Solutions: 1.1, 1.2

Jieting Assignment2 Reminder.jpg

  1. Reminder that is set earlier on will be activated on user's phone at a designated time.
  2. Users can set a reminder on their own phone so that they will be reminded to pay/receive any amount they owe/are owed. This would help to ensure that payments are made and received promptly.
  3. Users can also set the amount to pay/receive together with the person they have to pay/receive from.

Inspiration 2: Voice Command Applications (Eg: Siri, Google Voice)

  • Solutions: 1.1, 1.2, 1.4, 1.5, 2.2, 2.3, 2.5, 3.1

Jieting Assignment2 Siri.jpg

  1. Voice Command has been known to be users' "intelligent personal assistant" which helps to get things done with a line of command[1].
  2. By using a voice command application like Siri, users can easily ask Siri to open up their calculators and do a calculation for them. As each line of command and response is being displayed on the screen, users will be able to see a step-by-step breakdown if they want to. Users also do not need to remember any values they get from intermediate steps and could refer back to the previous lines of command if they need to.

Inspiration 3: CamScanner -Phone PDF Creator

  • Solutions: 3.3, 3.4, 3.5

Jieting Assignment2 Scanner.jpg

  1. This application allows users to take a photo of a paper and convert it into a clear PDF format.
  2. Users can access the PDF format of their receipt via the website and they can make annotation on the PDF format. As the PDF format is on the website, users can easily share the PDF with anyone they like to and any annotations made on the PDF format would be seen by others. By doing so, users would be able to do their respective calculations and they can make sure that the final tabulated amount calculated by each individuals tally with the final bill amount.

Inspiration 4: Billr[2]

  • Solutions: 2.1, 2.4

Jieting Assignment2 Billr.png

  1. A simple bill splitting application available on both Android and iOS plactform
  2. Allow users to choose the method to split the bill - either splitting it evenly among all diners or split it based on respective meals.
  3. Allow users to key in the tax and tip amounts. However, this may not be that useful in Singapore where tipping are not common and tax amount are fixed.
  4. Such a simple bill splitting application helps users to split their bill by keying in the amount of the bill.

Inspiration 5: Online to-do task list

  • Solutions: 1.5

Jieting Assignment2 Task.png

  1. Google Task is one of the popular online to-do task list that sync the task together with Google Calendar. Being the most popular calendaring application[3], there is a high chance that every users use google calendar. Furthermore, both Google Calendar and Google Tasks allow users to share them with other users. Hence, users can make use of such a functionality on Google Calendar and Google Tasks and add the payment to receive/pay as a task. In addition, users can also share the task they have created with other users to ensure that both side would receive the reminder to pay and receive.


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