NENP : The Fuel Manager

Contact Form  |  Japanese


NENP (This is the Japanese word which means “fuel economy”) is a fueling management / fuel economy calculation application. You can record the fueling information for each vehicle (car or motorcycle) and automatically calculates the fuel economy.

There are many other similar apps, but NENP has the following features.

  • Simple and sophisticated user interface.
  • Calendar display of fuel economy or refueling amount.
  • You can register data by specifying the date from the calendar. This is useful for registering past data.
  • You can switch between trip input and odometer input, total input and unit price input.
  • You can exclude the price from management. The price column will disappear when entering fuel records and when viewing the list.
  • Automatically syncs and saves data to iCloud, so there is no need for backups. Once the data is saved to your device, it is automatically synced to iCloud, so you can use this app even in situations where data communication is not available.
  • The same data can be viewed/edited from multiple devices logged in with the same Apple ID (e.g. iPhone and iPad together).

Getting Started

  • First of all, you need to register your vehicle. Register your vehicle (car or motorcycle) by clicking on the button visible on the fueling record screen or the button on the upper right of the vehicle list screen. You will not be able to do anything until you have registered at least one vehicle. Register a thumbnail image if necessary.
  • [IMPORTANT] If you want to use trip meter value as distance, please select TRIP in the App Setting “Distance input method (Odometer or Trip)”.
  • After registration of the vehicle, tap the “+” button at the bottom of the screen to open the fueling information registration screen. By default, you are supposed to enter the odometer value, refueling amount, and total amount. If you want to change the input method, please change these settings in the “Settings” tab first.
  • Once you enter the odometer (or trip), refueling amount, or total amount, the data will be saved at that point. You do not need to enter all values to save the data. If you close the application without entering anything, the data will not be saved.
  • When you close the screen by clicking the X button in the upper left corner or swiping down, the record will be added to the “FUEL” tab. Note that the fuel economy information will not be calculated until the number of records exceeds a certain number.

Views and Functions

Fuel Tab

  • The Fuel screen displays the fueling record and fuel consumption information for each registered vehicle. If you have multiple vehicles registered, you can swipe left or right to switch between vehicles; if you have only one vehicle registered, you cannot swipe (disabled).
  • The top part of the screen displays the vehicle thumbnail image, vehicle name, and average fuel economy.
  • Tapping the thumbnail image will open the vehicle editing screen.
  • Average fuel consumption will not be calculated until a certain amount of data is available. If it cannot be calculated, it will be displayed as “-.–“.
  • When a certain number of refueling data is available, a line chart with max / min fuel economy will be displayed below the thumbnail image. In addition, a graph icon will appear on the right side of the fuel consumption data, and tapping this icon will open a screen showing the total fuel consumption and other statistical information (in vehicle units).
  • The icons on the left side of the refueling data mean the following
    • [GREEN ↗] Fuel economy has increased.
    • [RED ↘] Fuel economy has worsened.
    • [GRAY =] Same as last time
    • [YELLOW ×] Excluded
    • [DOTTED SQUARE] Do not calculate fuel economy (if the tank is not full, if there is too little data to calculate, or if it is the oldest and next oldest data)
  • When the tank is not full, “NOT FILLED” is displayed at the top of the fueling data.
  • When you tap the fueling data, the screen to modify the information will open. All items can be changed.
  • If you want to delete the refueling data, tap and hold it.

Refueling information registration / modification screen

  • If you have more than one vehicle registered, the vehicle information (thumbnail and name) will be listed at the top of the screen; if you have only one vehicle, it will not appear. You can change the vehicle by tapping here. This function is intended to change or correct the vehicle to be registered when the registration screen is displayed from a tab other than the “FUEL” tab, or when you have registered the record to the different vehicle by mistake.
  • Tapping on the date and time will bring up the date and time selection calendar. If you want to change it, please correct it here.
  • When you enter the odometer (or trip), refueling amount, or amount, the data will be saved at that point. You do not have to enter all values to save the data. If you close the application without entering any data, the data will not be saved.
  • If you select “NOT FILLED” when the tank is not full, the data will be excluded from the fuel economy calculation, and the fuel economy calculation will be put on hold until the next fill-up.
  • If you turn on “Exclude this from fuel economy calculation”, it will be excluded from the fuel economy calculation. This function is intended to prevent strange values from appearing in the average fuel economy in cases where the fuel economy is extremely high compared to normal, such as when the previous fueling information was not entered. For the values themselves, please input the actual values as usual. If you don’t, the calculation for the next time you refuel will be strange.

Calendar tab

  • The “Calendar” tab displays information on a calendar basis, with the color identifying which vehicle it is for. Which color is for which vehicle is shown in the list below the calendar.
  • The values displayed in the calendar are either fuel economy or refueling amount. You can specify which one to display from the settings screen.
  • The numbers displayed at the bottom of the screen are the total refueling amount and average fuel economy for the month.
  • Tapping on an item in the calendar will open a screen to modify that information. All items can be modified.
  • When you tap a date cell in the calendar, a + button will appear in the upper right corner. Tap the + button to open the fueling record screen, where you can add fueling information for that day. The time is set to noon, so you can modify it if necessary (usually you can leave it alone). Please use this function when you want to add a record calendar-based that has not been registered in the past. In this case, the vehicle that is displayed in the “FUEL” tab is selected. You can also re-select the vehicle on the Refueling Records screen.

Vehicles tab

  • You can register, edit, and delete vehicle information.
  • If you have multiple vehicles, you can drag and drop them to change the order. This order will match the order in the “FUEL” tab.

App Settings

  • Use total price or unit price : Select whether you want to input the price as total price or unit price. [default: Total price.]
  • Manage fuel price or not : If you want to purely manage the fuel economy, select “Do not manage price” to hide the item for price from the input screen and also from the list view. [default: Manage]
  • Select Filled by default?: If this switch is off, the default value of “Filled tank” is off. If you often do not fill up the tank, please select this option. However, if you do not filled the tank, it will not be included in the fuel economy calculation, so it will only be useful as a simple fueling history management [default: On].
  • Displayed value on calendar: Specify the fuel economy or Fuel amount as the value displayed in the calendar [default: Fuel economy].
  • Hide Chart when scroll: A line chart will be displayed on the Fuel screen when the number of fueling record reaches a certain level, but if you want to hide this graph when scrolling and increase the number of items displayed, turn it on [default: off]
  • Export to TSV file: Exports all data to a TSV file for each vehicle. A mailer will open and you can send it to yourself.

Additional Notes :
Change the units as necessary.

iCloud sync

NENP stores your data in the iCloud storage of the iCloud account that your iPhone is logged into. You don’t need to do anything in particular to have it sync automatically.

The synchronization process is performed automatically by iOS, not by this app. Once the data is saved on the iPhone, it is transferred and saved to iCloud. Therefore, you can save even if you are not connected to the network. When you go online, it will save to iCloud by itself.

If you use the same iCloud account on multiple devices (e.g. iPhone and iPad) and have NENP installed on each device, the data will be automatically synchronized (works as if you are referring to and updating the same data). If you make any changes on one device, the changes will be notified to the other device and it will automatically update the data, but it will not redraw the information displayed on the screen, so please pull the screen down or otherwise reload it.

Not only the data, but also the app settings are saved in iCloud. However, synchronization of settings (i.e., reflecting iCloud saved information to the device) is performed only when the app is launched. If you change some settings on one device and want to reflect it on another device, it is better to force close the app and then start it again.

The amount of data you can store in iCloud depends on the amount of space available in your iCloud account.

Import function (Ver 1.1 or later)

TSV files can be used to import fueling records in bulk. Importing is performed for each vehicle. There is no limit to the number of data that can be imported at one time.

The import function is intended for people who are reasonably familiar with using PCs, business systems, Excel, etc.

This feature is intended for those who have been recording data in Excel, text, other apps, etc. and want to migrate it to this app. Backups are automatically synced to iCloud, so there is no need to export and import for backup/restore purposes.

TSV file format

The TSV file format is the same as the file exported from this application. Therefore, it does not indicate any particular number of columns, column items, or order. Based on the exported TSV file, it is easy to describe the data you want to import.

As you can see, the first line is the header line and the rest are the data lines.The header line should be left as it is in the export file.The data line should be written based on the exported data.

The procedure for filling in each column is as follows. Some of them depend on the vehicle setting (Distance input method) and the application setting (Use total price or unit price / Manage fuel price or not).

  • Enter it in the same format as the export file. The time is required.
  • Fuel Economy:Please leave it blank as it will be calculated automatically. App will ignore anything you write.
  • Amount:Please fill in the amount of refueling.
  • Filled:Please enter “Filled” or “Not Filled”
  • Exclude:Please enter “Exclude” or “Include”
  • Trip:Fill in this field if the distance input method is TRIP METER. Ignored when ODOMETER input is used.
  • Odo:Fill in this field if the distance input method is ODOMETER. Ignored when TRIP METER input is used.
  • Total Price:If the price is to be managed and the input method is “Total price,” fill in this field. If not, leave it blank.
  • Unit Price:Price:If the price is to be managed and the input method is “Unit price,” fill in this field. If not, leave it blank.
  • Memo:If you have any memos, please fill them in. If not, leave blank.


The process is to send the edited file on the PC/Mac to the iPhone, then send it from “Mail” to “NENP” for importing. The details are as follows.

  1. Edit the TSV file on your PC/Mac or other device and send it as an attachment to an email address that can receive it on your iPhone. There are no rules for file names, but please make sure to use “.tsv” as the file extension.
  2. Open the email in “Mail” on your iPhone and open the attachment.
  3. Tap the share button in the upper right corner.
  4. You will see a screen to select the app to share. If NENP is there, select it. If not, tap “Other” on the right side of the screen and select NENP from the list.
  5. If you have NENP open, the application will switch. At this point, the TSV file has been copied.
  6. Tap “Import fuel record from TSV file” in the App setting tab.
  7. You will be prompted to select a file to import. Select the file you want to import and tap “Finish”.
  8. You will be prompted to select the vehicle you want to import. Make your selection and tap “Finish”.
  9. The importing process will start immediately. When you see “Done”, you have succeeded. Open the imported vehicle. If it is not reflected, pull the screen down and reload it. If you get a failure message, it is usually due to some kind of file entry error.
  10. Regardless of success or failure, the TSV file has been deleted.

Note that if you send a file from “Mail” to “NENP” repeatedly, a file will be created for it. There is no way to delete such a file. You can either leave the file as it is, or create an appropriate vehicle temporarily, import it into it, and then delete the entire vehicle.


You can use contact form to send mail to developer to ask a question, send a bug report and so on.