What are your best practice recommendations for working with different file types?

Hardware Performance

Different iPad and Mac devices have different combinations of hardware that can affect performance, which in turn affects how well an app can carry out certain functions. The processor and memory are the main factors that affect performance. Generally speaking the newest devices will offer the best performance as they will have the latest processors and more memory (RAM).

While each release of our apps are stress tested against some of the most resource intensive content, and the code is optimized to take full advantage of the latest processors, these guidelines regarding file types will help ensure that you do not reach the limitations of your device.


PDF Documents

PDF Documents are unique in that they can contain many different types of content. Identifying files that can cause performance issues is not simply a matter of the file size in MB. A compressed file (of just a few MB) of a high resolution image will consume just as much RAM when displayed as the uncompressed counterpart at the same resolution. In addition, a large (in dimensions) line drawing (such as an architectural CAD file) may be very small in file size, but require a lot of processing power to display.

Due to the free-form nature of PDF files, there is no single fix for every file. However, most issues can be resolved by following these guidelines:

Scan documents at 150 dpi to 300 dpi for optimal performance. Scanning higher than 300 dpi offers little in terms of quality and significantly increases performance requirements.

Resample existing documents that are over 300 dpi, to 150 dpi to 300 dpi before importing. This can be done with Adobe Acrobat’s “Preflight” feature. (Note that other third-party PDF programs, such as Power PDF, have been known to cause issues in many apps and are not recommended.)

Where possible, use original PDF documents instead of scanned or flattened copies. Scanned or flattened documents are essentially a photographic representation of textual content, and in turn take up more space, consume far greater resources when displaying, and typically do not look as clear on screen (especially when zooming or creating callouts). Original PDF documents can also contain OCR data that can be searched.

We have found that PDFs optimized with the Mac Preview app tend to be the most compatible, displaying faster, and using less memory. You can optimize a PDF file in Preview by following these steps:

  1. Right click on your document and select “Open With”, then choose “Preview”.
  2. Choose “Export…” from the “File” menu (NOT “Export as PDF…”).
  3. Select “PDF” as the Format, and “None” for the Quartz Filter.
  4. Make sure that the checkbox next to “Create Linearized PDF” is selected.
  5. Save the document with a new name in order to preserve the original.

You can also use Adobe Acrobat to perform a similar procedure, and do it to multiple documents in one step.


TIFF Images

TIFF images are single-page or multi-page image files which typically contain scanned document content. It is recommended that you follow the PDF guidelines with regard to dpi and ensure the resolution is 300 dpi or less. TIFF images can be scaled in the Mac Preview app by selecting the pages of the TIFF in the thumbnail pane, then choosing “Adjust Size” from the “Tools” menu.



Digital and smartphone cameras have the ability to capture photographs at very high resolutions. For stability and performance while presenting, TrialPad will reduce large images during the import process to be no larger than 4096 x 4096 pixels. For optimal quality, and to reduce time and bandwidth required for importing files, you should scale your images so they match, or are slightly higher, than the resolution of your external display if the document will need to be enlarged during presentation. For example, an image to be presented on a 1080p display should fit within a 1920 x 1080 area.

Crop images that have excess “canvas” or irrelevant content. This will not only help reduce bandwidth and processing time, but it will also give your audience a clearer view of the relevant content.

Crop areas of an image that you know you will want to zoom into. If you have high resolution images that contain content you will want to magnify more than 2X, consider importing additional cropped copies of the image so that you can retain a higher resolution of those portions, while optimizing the performance and storage capacity on your device.


Text Files

Text (TXT) files are typically very lightweight and performant, therefore there are no special considerations for importing these types of files.


ZIP Files

Our apps gives you the ability to import ZIP files containing files and folders, and maintain their file and folder structure, thereby reducing the need to reorganize them after importing.

The following guidelines are strongly recommended when creating ZIP files:

  1. Keep your ZIP files under 1 GB. If you have more than 1 GB of content, split it up into multiple ZIP files, and/or import your multimedia separately.
  2. Do not include ZIP files within ZIP files as this scenario is not supported.
  3. Only include supported files within your ZIP file. Files that are not supported will not be imported, but will increase the amount of time it takes to import the ZIP file, and the amount of storage needed to extract and process the ZIP file.

While the ZIP file itself is discarded after the contents are extracted, make sure you have enough space on your device to temporarily store both the ZIP file and it’s un-compressed contents (this will likely be more than twice the size of the ZIP file itself).


Video Files

For the best experience, the following steps are highly recommended prior to importing video content:

  1. Clip videos prior to importing. This will save time and/or bandwidth when copying files to your device, save large amounts of storage space on your device, and result in higher quality videos when imported from your photo library.
  2. Remove any un-needed videos from your cases. Video files can take up large amounts of space, and storing unnecessary video in your cases can cause your device to run out of storage space.


Audio Files

TrialPad supports importing and playing back audio files that are compatible with iPadOS.